Sulphur denitrator and sulphate production.

[Belgian Anthias]

Using a sulphur denitrator is linked to sulphate production. For each mol nitrate removed by the sulphur bacteria 1.1 mol sulphate is produced.
In a BADES (Biological Autotrophe Denitrification using elemental Sulphur) system less than the theoretical amount of sulphate is produced. Also in SLAD ( Sulphur Limestone Autothropic Denitrification) systems less sulphate is produced. This can be explained because part of the nitrate is removed by heterotrophs. Others have reported much higher sulphate productions. They used batch reactors and when the batch stays to long in the reactor a lot of H2S is produced which is recycled to S and/or SO3. This can be avoided by using constant flow reactors. Also in a normal BADES system H2S is formed and recycled but in much lower quantities. The amount S or SO3 produced depends of the sulphide/nitrate ratio in the biofilm layers. The amount nitrate entered can easily be adjusted.
As nitrate shortness will occur in every batch, batch reactors can not be advised when sulphate production is an issue.

When a BADESSystem is used a lot of nitrate can be removed at a low nitrate level which needs a high flow and a lot of DO is entered into the reactor. It is published that the sulphur can be oxidized to sulphate without reducing nitrate using the DO available which is a big disadvantage because off the elevated and unnecessary sulphate production.

When a BADES reactor is in balance the bio-film will have thick oxygen consuming outer layers which will consume enough oxygen to make the lower layers an OMZ ( Oxygen Minimum Zone) ideal for dentrification by Thiobacillus denitrificans and Sulfurimonas denitrificans. To have a good working reactor flow is adjusted in a way that enough nitrate can be entered to remove the daily nitrate production daily without entering to much oxygen. For to make this possible the reactor must be big enough and the volume is matched with the nitrate removal rate. As T.denitrificans grows in the layers on the substrate, no or little dissolved oxygen can be used even when they are able to.

Investigations of the biofilm on a sulphur particle have shown that most of autotrophe denitrification on sulphur is done by the T.denitrificans and S. denitrifans families. 30% to 50% of the biofilm on the sulphur substrate was recently identified to be member of the T.denitrificans family. +- 40% of the biofilm consists of bacteria whose task is recycling and renewing the biofilm itself, green sulphur bacteria and others.
In a BADES reactor the outer layers of the biofilm may contain autotrophe nitrifiers helping reducing oxygen and eleminating ammonia. As heterotrops use the biomass available from the biofilm itself they are important for the recycling and renewal of the biofilm while reducing DO or nitrate.

Adding any form of organic carbon will disturb this balance and the autotrops will be outcompeted by the heterotrops causing the biofilm to transform. When the dosed organic carbon is consumed the biofilm needed will be gone for some time. Adding VODKA can have a huge effect on the nitrifying and denitrifying capacity of an aquarium system, certainly when bio-filters are used.

From T;denitrificans it is known for some time that they can use both known ways for building up it's cells and membranes, the RuBisCo I form and the RuBisCo II form, the way enzymes are used in the Calvin Cycle. They can do this both ways anaerobically but it was not known if they could use both ways aerobically.

Now it is published they can grow aeroob on thiosulphate, tetrathionate en thiocyanate and they are also able to grow anaeroob on thiosulphate, tetrathionate, thiocyanate, sulphide or elemental Sulphur.

https://microbewiki.kenyon.edu/index.php/Thiobacillus_denitrificans

This means they are NOT able to use oxygen while growing on elemental sulphur and sulphide.

This means also that the amount of elemental sulphur in a sulphur denitrator has no or very little influence on the sulphate production which confirms our experience in practice.

A BADESS is able to close the nitrogen cycle within a closed aquarium system by removing the daily nitrate production daily.

[MaLi]

Belgian, many thanks for your effort, but is Saturday morning and you wrote a semi-academic explanation. A bit too much for me at this time ... but interesting.
So what's your conclusion ? Tanks with a sulfur denitrator should or should not be dosing carbon ? or carbon + vinegar ?

cheers,
MaLi

[CHSUB]

from the link:
"The optimum conditions for denitrification are pH 6.85 at 32.8°C, while the optimal growth conditions are pH 6.90 at 29.5°C."

adding calcium media to the reactor appears to be a mistake. having that media condition the effluent after the sulfur in a second reactor is a better idea, if the above is true.

[tmz]

Seems to me the aragonite( calcium carbonate media) could also provide a colonizing area for heterotrophic bacteria when organics are available to them which is often the case even without carbon dosing.

[CHSUB]

Seems to me the aragonite( calcium carbonate media) could also provide a colonizing area for heterotrophic bacteria when organics are available to them which is often the case even without carbon dosing.

possibly, however i would suspect aragonite would increase the pH out of the optimum range for the listed bacteria?

[tmz]

I think we are in agreement; I don't use or advise using calium carbonate in sulfur denitrator . Providing surface area for hetertrophic bacteria there is not a positive ,IMO. There is also the matter of extra calcium added when calcium carbonate dissolves

[Belgian Anthias]

Belgian, many thanks for your effort, but is Saturday morning and you wrote a semi-academic explanation. A bit too much for me at this time ... but interesting.
So what's your conclusion ? Tanks with a sulfur denitrator should or should not be dosing carbon ? or carbon + vinegar ?

cheers,
MaLi


Why one should use VODKA when a sulphur denitrator is in use which removes the nitrate production?
Why dosing carbon in a sulfhur denitrator?
Some have advised to ad carbon to boost the start up of the reactor.!?
A BADESSystem reduces nitrate to nitrite within 24 h and will produce N2 after +- 8-12 days without adding carbon. I do not know if it will be faster adding carbon but I am pretty sure it will NOT.. ( carbon based denitrators need 3-4 weeks and more to start up)
To become a good working BADESSystem a good balanced biofilm must be cultivated.
Adding carbon makes this impossible. So my conclusion is NO!

[bertoni]

The carbon might outcompete the sulphur denitrator for fuel, depending on the amount added, but either way, the nitrate level should go down.

[Belgian Anthias]

A BADESSystem is build up with minimum 2 fluidized reactors. One with sulphur and one with calcium carbonate media. Both reactors have the same volume. The reactors can be plumbed in in series or parallel or used both or mixed ways. For a reefaquarium we use them in series.( the daily nitrate removal rate =<2ppm daily) When a CO2 calcium reactor is present it can easily be modified.
Two reactors because only a small amount of sulphur is used and the calcium reactor must be cleaned and serviced at a much higher frequency. Mixing the media is possible but this means the sulphur reactor must be opened to add and clean calcium media and restarted. An other and more important reason is the structure of the biofilm. On a sulphur particle all processes can take place as it is not only the base for the biofilm but also a substrate for growing the bacteria we want to cultivate.
In SLAD systems sulphur and limestone( 25-50%) is mixed and needs a lot more service as the limestone disintegrates and clogs together.
In SLAD systems plaster ( sulphate?) was found to be one of the problems.

In reef aquarium systems only a small amount of nitrate has to be removed daily, mostly not more as 2mg/l daily, our concern is not the optimum PH for the bacteria as they are able to remove more than enough in the normal working range of the sulphur reactor.
Our first concern is that all alkalinity loss is compensated.
The calcium reactor will compensate for all alkalinity loss( nitrification and denitrification) and add some calcium. A reef aquarium system consumes a lot more calcium as will be added..

The effluent from a BADESSystem has to be aerated to remove CO2 and stabilize alkalinity and PH.
In closed aqua-culture systems bio-skimmers filled with oyster shell grit ( marine systems) are often used for this purpose. Marine aquarium systems can use the skimmer already present.

The calcium reactor may also hold back some sulphate which brings us back to the title of the thread .

What happens in the calciumreactor of a BADESSystem? How sulphate may be hold back?

[bertoni]

I don't think that sulfate production can be prevented. It's an inherent part of the anaerobic metabolism involved.

[Belgian Anthias]

The carbon might outcompete the sulphur denitrator for fuel, depending on the amount added, but either way, the nitrate level should go down.

Why?

The nitrate level goes down when more as the daily nitrate production is removed every day.
To keep the level steady the nitrogen cycle has to be closed.

The suphur denitrator will stop functioning as a sulphur denitrator and denitrification from heterotrophs will be minimal or nihil. How the daily production will be removed?
,

[Belgian Anthias]

Just to clear some things out.

A BADESS is a system with a reactor filled with elemental sulphur as base and substrate for the biofilm. It is NOT comparable with a carbon based denitrator and is managed at a complete different way. The reactor is NOT kept annoxic (<0.5ppmDO) .

Sulphur-reactors where the flow is limited to limit the DO entered for keeping the reactor anoxic (-0.5ppmDO) can only reduce a limited amount of nitrate and the nitrate removal rate is not or very difficult to manage. At low nitrate levels, reactors managed this way only can reduce a very small amount of nitrate.

A BADES-reactor used in a BADESSystem is operated at a daily flow true the reactor of one to two times the systems total volume. This makes it possible to remove the daily nitrate production daily and close the nitrogen cycle at low nitrate levels. Once the reactor is in balance at the nitrate level desired the reactor will become self-regulating. To be able to do this the volume of the reactor is based on the daily nitrate removal rate.

Any sulphur reactor based on the advice given by Longouet is able to do this. The reactors are modified with a closed loop to become fluidized reactors. http://recifal.fr/chimie-de-laquarium-recifal/

The BADES reactor can be managed as a normal bio reactor at a normal flow, a reactor where nitrification can take place. Than the flow is corrected to induce some partial nitrification. This occurs when the oxygen level has descended to +- 2ppm and less. At that moment the inner biofilm layers on the sulphur substrate will become an OMZ (Oxygen Minimum Zone) and denitrification by autotrophe bacteria can take place using the sulpur substrate to grow. Now the flow may be corrected to remove the daily nitrate production daily. ( between one to two times the systems volume daily)
As partial nitrification can be induced it may be possible to bypass the steps to nitrate and back.
I do not know if this takes place but it is possible to induce autotrophic denitrification by managing the reactor this way.

[bertoni]

Why?

The nitrate level goes down when more as the daily nitrate production is removed every day.
To keep the level steady the nitrogen cycle has to be closed.

The suphur denitrator will stop functioning as a sulphur denitrator and denitrification from heterotrophs will be minimal or nihil. How the daily production will be removed?
,
I'm not sure what you mean, but whether the nitrate is removed by bacteria via carbon dosing or via the sulfur reactor, the tank's nitrate level still will decrease. If the reactor isn't doing much, that's okay. Same for the carbon.

[Belgian Anthias]

I'm not sure what you mean, but whether the nitrate is removed by bacteria via carbon dosing or via the sulfur reactor, the tank's nitrate level still will decrease. If the reactor isn't doing much, that's okay. Same for the carbon.

Carbon dosing does not remove nitrate. The cultivated bacteria assimilate some nitrate and phosphate,, some can take up more as needed to build up there cells. Nothing is removed so far.
Some of these bacteria are taken up, others are removed with a skimmer, some die and the nitrate and phosfate is released back in the system. The nitrate removal rate is very small and not predictable.

When carbon ( VODKA) is dosed when bio-reactors are used the reactors may turn into a slimy mess which can not be removed by back washing. Autotrophe bacteria may be outcompeted and die off. OMZ zones may turn hypoxic due to the sudden increase of DO consumption, also in the aquarium, DSB and living stone. The effect on nitrification and denitrification in de aquariumsystem may be huge and the found balance may be lost completely.
May be!? All nitrate removal methods have there caveats!
Dosing carbon? Not when I have a sulphur denitrator!

Removing a bit of nitrate is not the same as lowering the nitrate level. That depends of the daily nitrate production.

The nitrate level will NOT decrease because some nitrate is removed, only when more as the daily production is removed daily.

A BADESSystem needs a constant supply of nitrate and oxygen to sustain the biofilm.

If it is OK that the sulphur denitrator isn't doing much, why using one?

[bertoni]

Carbon dosing seems to work by using the skimmer to export the nitrate, but it might facilitate denitrification more directly as well. A lot of people have had success with it, but I suppose there's some chance it's a placebo effect.

If the carbon dose is too small to remove all the nitrate from the system, then the sulfur reactor might be able to process the rest. Since some tanks don't do well with larger carbon doses, a hybrid approach might be useful, or such tanks likely would be fine with just the sulfur reactor. I agree that if the carbon dosing is removing all the nitrate, then the sulfur reactor won't do much, and could be removed from the system, at least until the tank nitrate product rate increases.

[Belgian Anthias]

BADESSystems are used to keep a low nitrate level (<1ppmNO3-N) and remove a lot of nitrate daily the same time .(1ppmNO3-N can easily be maintained while removing 4-8ppm nitrate daily) The nitrate removal rate is predictable and can easily be controlled and adjusted by the user. The nitrate level is controlled at the level as desired by the user. (a minimum level is required to sustain the biofilm) This makes it possible to manage the nitrate in a closed mixed reef aquarium with SPS, LPS, leathers, and a high bio-load and feeding requirements.

[Belgian Anthias]

Carbon dosing seems to work by using the skimmer to export the nitrate, but it might facilitate denitrification more directly as well. A lot of people have had success with it, but I suppose there's some chance it's a placebo effect.

If the carbon dose is too small to remove all the nitrate from the system, then the sulfur reactor might be able to process the rest. Since some tanks don't do well with larger carbon doses, a hybrid approach might be useful, or such tanks likely would be fine with just the sulfur reactor. I agree that if the carbon dosing is removing all the nitrate, then the sulfur reactor won't do much, and could be removed from the system, at least until the tank nitrate product rate increases.

A sulphur denitrator can not function properly as a sulphur denitrator when carbon is dosed. The reactor will not be able to remove the rest. A sulphur denitrator needs nitrate to build up its biofilm. It is not a system that can be turned ON and OFF as suitable.
Dosing carbon when a sulphur denitrator is functioning may turn the reactor into a slimy mess which will not work any more.
There is no reason why carbon should be dosed when a sulphur reactor is in use.

Carbon dosing may facilitate heterotrophe denitrification but the sudden growth may also clog the stone and DSP,and prevent nitrification of ammonia. It may even stimulate nitrogen fixation by cynobacteria and they will release this nitrogen as ammonia when they die and decompose.

As the nitrate removal rate is NOT predictable or controllable the carbon dosing method can not be used for managing the nitrate level, something that can be done easily when using a sulphur denitrator.
No other nitrate removal method I know about gives full control to the user over the nitrate removal rate and the nitrate level in the system.

[Belgian Anthias]

As most caveats for using a sulphur denitrator have been solved there is still the sulphate production. It is not a problem that has to be solved as there is enough sulphate in seawater and the amount of sulphate seems to have no or very little influence but it keeps me busy.
We know that sulphate may be hold back in the calcium reactors but how and why?
The sulphate production can be limited by managing the H2S/nitrate ratio which is done by providing a constant supply of nitrate.

The sulphate production can be reduced by inducing partial nitrification which allows to bypass the step to nitrate and back to nitrite. This is done and tested for ANAMMOX reactors. it is easily done by managing the flow. If the flow is managed to induce partial nitrification we can not manage the nitrate removal rate any more.
Taking in account the small amount of sulphate involved this will not be the solution.

It is published that the calciumreactors hold back most of the sulphate of a system with 850 kg sulphur. How this amount of sulphate is hold back. Thus it turn into plaster?

[bertoni]

A sulphur denitrator can not function properly as a sulphur denitrator when carbon is dosed. The reactor will not be able to remove the rest. A sulphur denitrator needs nitrate to build up its biofilm.
I'm not sure why you believe this. To keep operating, a sulfur denitrator will need some nitrate as input, but I don't see why a small carbon dose necessarily would make a reactor fail if there's still nitrate in the system. If the carbon consumes all the nitrate, then the reactor would stop functioning until such time (if ever) that the nitrate production increased beyond the capacity of the carbon dosing to remove it.

[Belgian Anthias]

I'm not sure why you believe this. To keep operating, a sulfur denitrator will need some nitrate as input, but I don't see why a small carbon dose necessarily would make a reactor fail if there's still nitrate in the system. If the carbon consumes all the nitrate, then the reactor would stop functioning until such time (if ever) that the nitrate production increased beyond the capacity of the carbon dosing to remove it.

Not even in my dreams!

A sulphur denitrator is based on the activities of autotrop bacteria which do not need organic carbon to grow. That is why sulphur is used as a base for the bacteria and as substrate.

WHY USE CARBON DOSING? What is the suspected benefit?



The big benefit of using a sulphur denitrator is that the flow can easily be managed. autotrophe denitrification starts at DO<3ppm. heterotroph denitrification at DO<0.4ppm. This makes it possible to use much higher flow rates and use the reactor at very low nitrate levels and still remove enough nitrate to remove the nitrate production. When carbon is dosed this advantage will be lost.

The good functioning of a BADESSystem depends of a good balanced biofilm where the outher layers consume oxygen and may nitrify ammonia. Due to the oxygen consumption there will be not enough oxygen available in the bottom layers for aerobe activities, an OMZ is created. The lack of enough oxygen makes it possible for the sulphur bacteria to reduce nitrate. All this is done by autotrops who will be outcompeted when carbon is dosed. When not enough oxygen and nitrate can be transferred true the layers for all bacteria and support growth some will starve and this biomass is recycled. H2S will be formed which will be recycled to S or SO4. Heterotrops will help recycling the biomass. This is normal.

When carbon is dosed the outher layer will grow explosive, outcompete the nitifyers, consume so much oxygen that even the middle layers will starve as a lot of the activities in those layers are aerobe and nitrate can not penetrate the bottom layers any more. The heterotrops will take over. Green sulphur bacteria may become the main habitants of the biofilm. De biofilm needed will be gone.
As the biofilm is out of balance parts or most of it will come lose from the substrate and even may clog the filter.

The sulphur reactor in a BADESSystem is NOT kept annoxic( <0.5ppmDO) and thus more than only reduce some nitrate, it gives full control over the nitrate removal rate and the nitrate level.

[Belgian Anthias]

Supposed that CaSO4 formation is one of the reasons why sulphate is held back in the calcium reactors. Seems to be the main reason why SLAD systems have to be cleaned frequently.( SLAD systems are used to remove nitrate for drinking water.)
For each 100 mole NO3-N, 88 mole Ca is produce ( Zhang)
This makes it possible to remove 4/5 of the 110 mole sulphate produced.
Seawater is easily over saturated. The influence of the PH increase in the reactor?

[tmz]

Now it is published they can grow aeroob on thiosulphate, tetrathionate en thiocyanate and they are also able to grow anaeroob on thiosulphate, tetrathionate, thiocyanate, sulphide or elemental Sulphur.

https://microbewiki.kenyon.edu/index..._denitrificans

This means they are NOT able to use oxygen while growing on elemental sulphur and sulphide.

This means also that the amount of elemental sulphur in a sulphur denitrator has no or very little influence on the sulphate production .


This above is from post #1is a student page submission to wiki link , unreviewed.So I'd take it with a grain of salt.

FWIW, thiosulfate and tetrahionate are sulfur oxyanions ,a potential source of oxygen.

It doesn't seem to follow that aerobic activity can't occur on a bed of sulfur given free oxygen in the water absent those oxyanions or that they won't form there.

[tmz]

As the nitrate removal rate is NOT predictable or controllable the carbon dosing method can not be used for managing the nitrate level, something that can be done easily when using a sulphur denitrator.
No other nitrate removal method I know about gives full control to the user over the nitrate removal rate and the nitrate level in the system.



Not true.



Dosing soluble organics to control nitrate and phosphate is very predictable and controllable, in my 6 years plus experience with vodka and vinegar dosing, using a set maintenance dose for a specific aquarium. The facultative heterotrophic bacteria take nitrogen primarily from ammonia in a one step aerobic process thus limiting nitrate production via ammonia oxidation. Some anerobic nitrate reduction occurs in the biofilm and in other hypoxic areas as well ,some nitrate assimilation also occurs. These facultative bacteria also take up a lot of PO4 as well. The food web is also enhanced as inorganic nutrients are converted to organic forms which are consumable and exportable via skimming .

A sulphur dentrator is also controllable in terms of optimizing anaerobic nitrate reduction depending on the amount of sulfur in use and flow though the denitrator to control the amount of oxygen and nitrate available vs the nitrate level in a system at a particular time .

[bertoni]

Not even in my dreams!
I'm not sure what you think is impossible or why.

WHY USE CARBON DOSING? What is the suspected benefit?
It's one way to reduce nitrate and potentially feed organisms like sponges.

[Belgian Anthias]

As the nitrate removal rate is NOT predictable or controllable the carbon dosing method can not be used for managing the nitrate level, something that can be done easily when using a sulphur denitrator.
No other nitrate removal method I know about gives full control to the user over the nitrate removal rate and the nitrate level in the system.



Not true.



Dosing soluble organics to control nitrate and phosphate is very predictable and controllable, in my 6 years plus experience with vodka and vinegar dosing, using a set maintenance dose for a specific aquarium. The facultative heterotrophic bacteria take nitrogen primarily from ammonia in a one step aerobic process thus limiting nitrate production via ammonia oxidation. Some anerobic nitrate reduction occurs in the biofilm and in other hypoxic areas as well ,some nitrate assimilation also occurs. These facultative bacteria also take up a lot of PO4 as well. The food web is also enhanced as inorganic nutrients are converted to organic forms which are consumable and exportable via skimming .

A sulphur dentrator is also controllable in terms of optimizing anaerobic nitrate reduction depending on the amount of sulfur in use and flow though the denitrator to control the amount of oxygen and nitrate available vs the nitrate level in a system at a particular time .

I will not start a discussion again.

I have to remove 1 ppm nitrate daily to keep the level steady at 1ppm.
How much VODKA ( organisic carbon) do I have to dose?

Adding VODKA will only remove an unknown small quantity of nitrate and the removal rate is NOT predictable at all and can not be calculated. The limited nitrate removal (limited by the max dose) depends of the uptake ( not removed, comes partially back into the system), the skimmer ( removed) and natural death. ( back into the system)

VODKA dozing thus not interest me at all. From my point of view it is considered as unreliable and even dangerous.

How sulphate is held back in the calcium reactors, that is what keeps me busy for the moment? As the calcium reactors are OMZ they could be used for BPR (Biological Phoshate Removal) but that should be part of an other discussion.
All caveats using a BADESSystem ( the reactor is NOT kept annoxic) are solved for me. After about two decades of using BADES sulphate was never considered as a problem.

[Belgian Anthias]

Now it is published they can grow aeroob on thiosulphate, tetrathionate en thiocyanate and they are also able to grow anaeroob on thiosulphate, tetrathionate, thiocyanate, sulphide or elemental Sulphur.

https://microbewiki.kenyon.edu/index..._denitrificans

This means they are NOT able to use oxygen while growing on elemental sulphur and sulphide.

This means also that the amount of elemental sulphur in a sulphur denitrator has no or very little influence on the sulphate production .


This above is from post #1is a student page submission to wiki link , unreviewed.So I'd take it with a grain of salt.

FWIW, thiosulfate and tetrahionate are sulfur oxyanions ,a potential source of oxygen.

It doesn't seem to follow that aerobic activity can't occur on a bed of sulfur given free oxygen in the water absent those oxyanions or that they won't form there.

T.denitrificans can not grow on elemental sulphur using free oxygen.

T.d. are able to use both forms of RuBisCo, the way enzymes are used to attain carbon from CO2 and building up there cells and membranes. Most bacteria can only use one form. T.d. can only use both ways in anaerobic mode and can grow on sulphur compounds aerobically but when growing on elemental sulphur they need both ways. That is what makes the bacteria very special.

Read the references for the wiki page which are approved and this:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC107408/

The findings are in line with what is experienced in practice. We now know also why!

Some drinking water plants use thiosulphate to induce autotrophe denitrification because of the higher possible nitrate removal rate. Tests have shown a higher sulphate production in correspondence with the nitrate removal rate. This may be because DO is used by T.d. (vacuum degassed water may still contain 0.5ppm to 2ppm DO) instead of nitrate which is wasting thiosulphate and the sulphate production may become problematic for drinking water. When elemental sulphur is used a lot less sulphate is produced.

Now the focus should be on the sulphate that is produced and held back in the calcium reactors of a BADESSystem.

[Belgian Anthias]

[B].

A sulphur dentrator is also controllable in terms of optimizing anaerobic nitrate reduction depending on the amount of sulfur in use and flow though the denitrator to control the amount of oxygen and nitrate available vs the nitrate level in a system at a particular time .

Not correct. Just a summary of all parameters.

[Belgian Anthias]

One can not have control over the nitrate removal rate when the nitrate reduction is optimized by limiting the flow for keeping the sulphur reactor annoxic (<0.5ppmDO). At low nitrate levels, reactors managed this way can only reduce a small amount of nitrate which all users of such a system know. The nitrate removal rate can not be adjusted to correspond with the daily nitrate production because flow corrections will bring the reactor out of balance as the cultivated biofilm has no or very limited oxygen consuming outer layer. These reactors are very vulnerable and easily mismanaged.

Reducing some nitrate is not the same as reducing the nitrate level. Controlling the nitrate level means that one is able to remove what is produced, the cycle is closed.

A BADESSystem gives control to the user over the nitrate removal rate, the daily nitrate removal and the nitrate level. Managed correctly the nitrogen cycle may be closed in a closed aqua-culture system. Once in balance on the by the user desired nitrate level, the BADES system is self-regulating. A BADESSystem is based on the daily to remove nitrate production.

No other nitrate removal method I know about is able to do that.

When the normal sulphate production is held back in the calcium reactors the influence on the aquarium system will be practically nihil. It is known it happens and reported by different sources.
Does it depends of the calcium media used? PH? Amount calcium in the water?Alkalinity?

[Belgian Anthias]

I'm not sure what you think is impossible or why.


It's one way to reduce nitrate and potentially feed organisms like sponges.

Thrue

In a nutrient rich system, sponges will find more than enough food.
As a BADESSystem is supposed to be used in a nutrient rich system proper feeding is no problem. That is one of the main reasons why a BADESSystem is used, to make it possible to maintain a nutrient demanding mixed reef aquarium.
In a nutrient rich aquarium system there is already a lot of organic carbon available, why adding more and destabilize the biological balance?
A sulphur denitrator will, when properly managed, easily remove all nitrate that is produced.
Mineralization, nitrification, denitrification and removal by a skimmer must be kept in balance. The skimmers function is to minimize mineralization by removing organic waste and the same time stabilize the PH of the effluent of the sulphur denitrator. The skimmers function may be limited to that, no need for stripping the water completely.
No need for more organic carbon.

Back to the sulphate removal?

[tmz]

I will not start a discussion again.

Then why did you?

I have to remove 1 ppm nitrate daily to keep the level steady at 1ppm.

So , on a given day you think your tank always produces 1ppm of nitrate and other tanks produce it at a set rate all of the time . IME, that varies based on a myriad of activities in a tank . I don't think you really know how much nitrate you are actually removing except,to borrow your words , in your dreams.

How much VODKA ( organic carbon) do I have to dose?



I'm not fond of wasting time and effort answering rhetorical questions, particularly in a false disingenuous context. The dosing rate I use as well as the varying rates used by others have been posted hundreds of times(35ml 80 proof vodka plus 80 ml 5% acetic acid vinegar daily for NO3 between 0 and .2ppm and PO4 at 0.02 to 0.04ppm in my case for a 650 heavily fed system) It varies from tank to tank until a maintenace dose is established as it does in the application of sulfur.

Adding VODKA will only remove an unknown small quantity of nitrate and the removal rate is NOT predictable at all and can not be calculated.

It is quite predictable and can be calculated on a tank specific basis which is how all methods should be managed. One size doesn't fit all whether it's a sulfur denitrator or carbon dosing,gfo etc.



The limited nitrate removal (limited by the max dose) depends of the uptake ( not removed, comes partially back into the system), the skimmer ( removed) and natural death. ( back into the system).



That makes no sense. It doesn't present a coherent view of organic carbon and it's role as a nutrient or the role of anaerobic nitrate reduction by faculatavie bacteria.

VODKA dozing thus not interest me at all. From my point of view it is considered as unreliable and even dangerous.

Your opinion; uniformed and misguided as it may be.

How sulphate is held back in the calcium reactors, that is what keeps me busy for the moment? As the calcium reactors are OMZ they could be used for BPR (Biological Phoshate Removal) but that should be part of an other discussion.
All caveats using a BADESSystem ( the reactor is NOT kept annoxic) are solved for me. After about two decades of using BADES sulphate was never considered as a problem.

Sulphate production is part of the reaction and overtime a buildup is likely to occur which will skew the chloride/ sulfate ratio away from natural levels. This is no a big problem with regular water changes and less so , when reasonable amounts of sulfur are used,IMO.

IME, sulfur denitrators are a useful tool for managing NO3,especially for reducing high starting levels ; so , is organic carbon dosing. I use them both on different systems depending on the goal.

Using them together will accelerate a reduction in the nitrate level in a an aquarium but may lead to problems with H2S and heterotrophic bacterial growth in the nitrate reactor if ethanol and /or acetic acid or by products get into the the dentirator. Some are trying combinatations and I'm interested in those outcomes.

[tmz]

Not correct. Just a summary of all parameters.

It is correct and to the point.

[tmz]

Reducing some nitrate is not the same as reducing the nitrate level. Controlling the nitrate level means that one is able to remove what is produced, the cycle is closed.



Odd statement;makes no sense to me.

Of course it is . The level of nitrate in a system is the concentration of nitrate in the sytem. Removing some reduces the level. " level : the degree of concentration of a substance in a fluid..." Websters

[Belgian Anthias]

I will not start a discussion again.

Then why did you?

I have to remove 1 ppm nitrate daily to keep the level steady at 1ppm.

So , on a given day you think your tank always produces 1ppm of nitrate and other tanks produce it at a set rate all of the time . IME, that varies based on a myriad of activities in a tank . I don't think you really know how much nitrate you are actually removing except,to borrow your words , in your dreams.

How much VODKA ( organic carbon) do I have to dose?



I'm not fond of wasting time and effort answering rhetorical questions, particularly in a false disingenuous context. The dosing rate I use as well as the varying rates used by others have been posted hundreds of times(35ml 80 proof vodka plus 80 ml 5% acetic acid vinegar daily for NO3 between 0 and .2ppm and PO4 at 0.02 to 0.04ppm in my case for a 650 heavily fed system) It varies from tank to tank until a maintenace dose is established as it does in the application of sulfur.

Adding VODKA will only remove an unknown small quantity of nitrate and the removal rate is NOT predictable at all and can not be calculated.

It is quite predictable and can be calculated on a tank specific basis which is how all methods should be managed. One size doesn't fit all whether it's a sulfur denitrator or carbon dosing,gfo etc.



The limited nitrate removal (limited by the max dose) depends of the uptake ( not removed, comes partially back into the system), the skimmer ( removed) and natural death. ( back into the system).



That makes no sense. It doesn't present a coherent view of organic carbon and it's role as a nutrient or the role of anaerobic nitrate reduction by faculatavie bacteria.


VODKA dozing thus not interest me at all. From my point of view it is considered as unreliable and even dangerous.

Your opinion; uniformed and misguided as it may be.

How sulphate is held back in the calcium reactors, that is what keeps me busy for the moment? As the calcium reactors are OMZ they could be used for BPR (Biological Phoshate Removal) but that should be part of an other discussion.
All caveats using a BADESSystem ( the reactor is NOT kept annoxic) are solved for me. After about two decades of using BADES sulphate was never considered as a problem.

Sulphate production is part of the reaction and overtime a buildup is likely to occur which will skew the chloride/ sulfate ratio away from natural levels. This is no a big problem with regular water changes and less so , when reasonable amounts of sulfur are used,IMO.

IME, sulfur denitrators are a useful tool for managing NO3,especially for reducing high starting levels ; so , is organic carbon dosing. I use them both on different systems depending on the goal.

Using them together will accelerate a reduction in the nitrate level in a an aquarium but may lead to problems with H2S and heterotrophic bacterial growth in the nitrate reactor if ethanol and /or acetic acid or by products get into the the dentirator. Some are trying combinatations and I'm interested in those outcomes.

We disagree?

VODKA dosing is unreliable, has a huge effect on the biological balance within the system
and I consider it as DANGEROUS. Carbon dosing is guessing work. ? When the question was asked to Peter Wilkins, the founder of the Berlin system, if he would consider carbon dosing and ad vinegar to his system he answered: " One must be crazy."
That was his opinion.

My opinion about carbon dosing was asked in combination with a sulphur denitrator, given and I explained why?

You have an other opinion and that is OK, I do not have to take the risks.

You claim that nitrate removal by VODKA dosing is predictable but can not answer a simple example question and you claim that I am wrong. When it is predictable it can be calculated. You have turned around the question.!
I do not need any explanation about carbon dosing any more, I will not use it!. Never! I have studied the method and based my opinion on founded information.This information and approved references can be consulted. Others will have an other opinion.

Controlling the nitrate level on the desired level is removing the daily nitrate production daily, every day.

This threat is about a sulphur denitrator, the sulphate production and caveats due to the use of it.


If you want to discus carbon dosing or bio-pellets or any kind of polymers there are enough threats on this forum. I have studied most of these methods. Non of them can replace a BADESSystem.

[Belgian Anthias]

Reducing some nitrate is not the same as reducing the nitrate level. Controlling the nitrate level means that one is able to remove what is produced, the cycle is closed.



Odd statement;makes no sense to me.

Of course it is . The level of nitrate in a system is the concentration of nitrate in the sytem. Removing some reduces the level. " level : the degree of concentration of a substance in a fluid..." Websters

Lessons in English now!?

Reducing is not the same as removing. Chemically when something is reduced it is added elsewhere. Assimilation is not reducing.

Any denitrification method can reduce nitrate. Assimilation removes nothing from the system. Some methods can lower the nitrate level, some can not. It is new for me that removing some nitrate is equal with reducing the level. Maybe for mister Webster but not for me. What if as at the same moment more nitrate is produced as removed? Nitrate production is a continuous process in a closed system. So, while removing nitrate it may be possible that the nitrate level increases or am I wrong again? Not in Websters? Logic thinking. Not so difficult. Not so odd?

Do you have nothing else to do than criticise? Maybe you can add something positive to the threat?

[Belgian Anthias]

When using a sulphur reactor determining the removal rate is very simple. Flow x nitrate level = nitrate removal rate at O nitrate effluent. ( this is not correct but close as it thus not take in account possible nitrification within the reactors)

As a BADESSystem is based on the daily nitrate production to remove, the system can remove the daily production every day and more if the level has to be lowered. The user can easily control the nitrate removal rate by adjusting the flow as the sulphur reactor used in a BADESSystem is not kept anoxic (<0.5ppmDO) The reactor must be big enough to be able to consume the amount of oxygen entered.

This way the level can easily be maintained below 1ppm NO3-N and remove 8ppm nitrate daily. The system has no limits, it is just an example. A BADES needs nitrate to keep the biofilm alive and in balance. It is supposed to be used in a nutrient rich environment and systems above 200 litre for easy management. For smaller systems it is more difficult to adjust the removal rate due to the low flow.

If someone has questions about a BADESSystem and the use of a sulphur denitrator I will be glad to answer them if within my ability.

[bertoni]

I don't know of any way to remove sulfate. A regular schedule of water changes should be more than enough to keep any problems at bay. Saltwater has a lot of sulfate in it as a starting point, so the amounts coming from a sulfur reactor should be irrelevant to most people.

[Belgian Anthias]

There are different ways to reduce sulphate in the water column.

A method used on industrial scale is sulphate precipitation (of mine water) by adding lime milk or kalkwasser (Calcium(di)hydroxide) This method is limited to remove sulphate concentrations above 2000mg/l (ppm). As there is more as 2000ppm sulphate in seawater this should be possible.

Another way is sulphate reduction. It is done on a industrial scale for example to remove nitrate and clean sanitary water in Hongkong where seawater is used to flush the toilets.The SANI systeem (Sulphate reduction, Autotrophic denitrification and Nitrification Integrated Process)
Sulphate reduction can also be used to remove nitrate from aquaculture systems. - Dissimilatory sulfate reduction. http://www.google.nl/patents/EP1718570A1?cl=en.
These processes need a lot of organic carbon (TOC). Although it can possibly be done in combination with BPR ( Biological Phosphate removal)

My research is now concentrated on precipitation to CaSO4 which easily can be removed when servicing the calcium-reactors.
Solubility of Calcium carbonate and precipitation of Calcium sulphate!? Adding lime or kalkwasser?

When this can be solved we have an easily and effortless manageable biological nitrate removal system that easily can close the nitrogen cycle without any caveats at all for the closed aqua- system.

In practice the sulphate production seems not to be a problem that needs a solution, even in a marine aquarium system where 850 kg sulphur is used,
Anyway it would be an advantage that drainage of sulphate produced by BADES into the system could be avoided or minimized more.

[Belgian Anthias]

I don't know of any way to remove sulfate. A regular schedule of water changes should be more than enough to keep any problems at bay. Saltwater has a lot of sulfate in it as a starting point, so the amounts coming from a sulfur reactor should be irrelevant to most people.

For most reef systems it will be irrelevant.

Using BADES in a nutrient poor system is more difficult to manage as only a small amount of nitrate can be removed.

Water changes are not a solution on the long term for mixed reef aquaria with a high bioload, even when done at a high frequency. At the end we end up with a semi-closed recirculation system. We still have to compensate for what is consumed and build up is only removed partially.
My opinion It is difficult to maintain a closed recirculating aqua-system with a high nutrient demand without bio-filters.

[bertoni]

I'm not sure what water changes won't do yet. I would keep up water changes no matter what the bio-load was.

[Belgian Anthias]

Not about reducing sulphate but about minimizing sulfate.

As we know of the composition of the biofilm on a sulfur particle, approximately 45% of the biofilm is occupied with the recycling of the biofilm itself. About half of these 45% are bacteria belonging to the same group as Desulfuromonas and are therefore heterotrophic anaerobic. Trichlorobacter thiogenes processes the dead biological material from the biofilm whereby H2S is formed due to lack of nitrate and the presence of sulfur. These bacteria are not able to reduce sulfate. They are located at the bottom of the biofilm. The H2S is then oxidized by autotrophic bacteria which make up the other half of the 45%, most of which belong to the group of green sulfur bacteria (17%), another part is facultative anaerobic, transformed into or SO4 or S and organic material. These bacteria mainly inhabit the middle layers of the biofilm. This organic material is then used as an energy source for chemo-heterotrophic bacteria in the middle and on the outside of the biofilm. (+ - 12% of the biofilm) where there is no shortage of nitrate or where they can use oxygen to mineralize organic matter.

We know that there ends up much less sulfate in the aquarium as is calculated. But is it calculated correctly ?

When nitrate is reduced using HS only 0, 77 SO4 is produced by T.denitrificans instead of 1.1 when using S.
When nitrate is reduced with HS only 0.625 SO4 is produced by green sulfur bacteria in the middle layers where sufficient nitrate is present and no sulphate at all is produced when a shortage of nitrate occurs but sulfur.

We speak of partial oxidation of sulphide and complete sulphide oxidation. In these latter processes nitrate is removed and H + originating from processed anaerobic activities.

5S2 + 8NO3 +8H+ ⇒ 5SO4 2- +4N2 +4H2 O

5S2 + 2NO3 + 12H2 ⇒ 5S0 + N2 + 6H2 O

(Sher, Yonatan, Kenneth Schneider, Carsten U. Schwermer, and Jaap van Rijn. "Sulfide-Induced Nitrate Reduction in the Sludge of an Anaerobic Digester of a Zero Discharge Recirculating Mariculture System "Water Research 42, No. 16 (October 2008)... 4386-92 doi: 10.1016 / j.watres.2008.07.03)

If we take into account the part nitrate which is reduced heterothrophically, the portion nitrate which is reduced using H2S in stead of elemental sulfur then we arrive at much less than 1.1 mole SO4 per mole of NO3-N. Deduct the amount of sulphate which precipitates in the calcium reactors, then there will not be so many left.

This corresponds with what is experienced.

it would be an advantage if the precipitation of sulphate could be managed but why bother?

[Belgian Anthias]

I'm not sure what water changes won't do yet. I would keep up water changes no matter what the bio-load was.

Using a BADESSystems eliminates water changes for nitrate control.

[bertoni]

Nitrate control is very low on my list of issues that might be solved with water changes. Maintaining ionic balance and removing refractory chemicals are much higher. Very few significant nitrate problems can be handled with water changes.

As far as using limewater to remove sulfate, that will work, but it also will remove magnesium and calcium, which is a major issue for saltwater tanks. The other method is interesting, and I'll have to read more. It might be interesting as an experiment, at least.

[Belgian Anthias]

Nitrate control is very low on my list of issues that might be solved with water changes. Maintaining ionic balance and removing refractory chemicals are much higher. Very few significant nitrate problems can be handled with water changes.

As far as using limewater to remove sulfate, that will work, but it also will remove magnesium and calcium, which is a major issue for saltwater tanks. The other method is interesting, and I'll have to read more. It might be interesting as an experiment, at least.

Sulphate reduction for nitrate removal is researched, tested and used for some time now.
The caveats are the same as for other organic carbon based systems.

For sulphate reduction only it can not be used in an aquarium system.
For me not an option.

[Belgian Anthias]

When 1 ppm nitrate NO3 is reduced to N +- 1.7 ppm sulphate may be produced.
When NO3 is reduced to 1ppm NO3-N, +- 7.55 ppm sulphate may be produced.

A big difference. How nitrate is measured ( test kit) and how the parameters are used for the calculation,
Different results although they are the same. when used correctly.

When 2ppm nitrate is reduced daily, after 100 days the calculated sulphate content may increase with 340 ppm. 1510 ppm when the parameters are mixed up. I made this mistake!

There is +- 2600 ppm sulphate present in natural seawater. Some salt mixes contain +-30 % less sulphate, some more. Dependable of the saltmix used, it may take one year for the sulphate level to reach the natural level using the example above. More than two years when 1ppm is removed daily. This when all nitrate is removed by the BADES proces. In practice this will be only for +- 75%.

Why bother?
For a mixed reef aquarium system using BADES will have only a very limited impact on the sulphate level and the sulphate level is not considered a concern.

Having full control over the nitrate removal rate and the nitrate level, being able to close and manage the nitrogen cycle in a closed system without any caveats for the aquarium system.
To good to be true?

[bertoni]

Hmm, 2 ppm of nitrate is a lot. I will need to go through the numbers, but sulfate is present at about 2700 ppm in saltwater, so some water changes should be fine to keep that rate of sulfate production under reasonable control.

If you are worried about sulfate, a denitrator coil might be the way to go.

[Belgian Anthias]

Hmm, 2 ppm of nitrate is a lot. I will need to go through the numbers, but sulfate is present at about 2700 ppm in saltwater, so some water changes should be fine to keep that rate of sulfate production under reasonable control.

If you are worried about sulfate, a denitrator coil might be the way to go.


2 ppm daily may be a lot for a reef aquarium that is kept at minimal nutrients. Not for mixed reefs with a natural look, with a lot of fish and other nutrient demanding animals, leathers, LPS etc... and fed life food. For fish only tanks and marine aquaculture systems.

I am not worried about the sulphate production of a BADESSystem.
It would be interesting though to know how precipitation of sulphate to plaster can be induced in seawater. How it is induced in the calciumreactor?

A water change using a salt mix with a low sulphate content will certainly aid in keeping everything under control.

Using a denitration coil is not an option due to a lot of caveats, nitrate removal is very unreliable and unpredictable. Very difficult to manage, nitrate removal rate can not be managed due to the very limited flow. And It can also produce sulphate but also reduce it.

[tmz]

You claim that nitrate removal by VODKA dosing is predictable but can not answer a simple example question

The question though rhetorical and silly( ignoring a myriad of variables as your "calculations" do) was answered responsibly and fully.

This threat is about a sulphur denitrator, the sulphate production and caveats due to the use of it.


If you want to discus carbon dosing or bio-pellets or any kind of polymers there are enough threats on this forum. I have studied most of these methods. Non of them can replace a BADESSystem.




I do not want to discuss carbon dosing since it's off topic in this thread other than to note it's a viable and useful method and can do perform as well as a sulfur dentrator in managing nitrates as well as phosphate, despite your uniformed assertions. You chose to bring carbon dosing into the discussion to attack it and misrepresent it;not me.

on that note:

When the question was asked to Peter Wilkins, the founder of the Berlin system, if he would consider carbon dosing and ad vinegar to his system he answered: " One must be crazy."



First of all the Berlin System work is from 1990, 26 years ago and counting as it's still a viable method . Second the quote you cite is without context meaningless and insulting ;folks that use carbon dosing with otr without the elements of the Berlin System are not "crazy". Third , the Berlin sytem does not include a sulfur dentirator; does it?


Do you have nothing else to do than criticise? Maybe you can add something positive to the threat?



:lol::lol:
That's hysterical given your historical and current propensity to dismiss any discussion that doesn't fit your ill conceived rules for a one and only way approach and to criticize other methods as "crazy and dangerous"


I do but you don't seem to handle the truth very well and tend to personalize the discussion;so, I try to limit my input to corrrecting misstatements of fact faulty extropolations, calculations and implications.

[tmz]

Lessons in English now!?

Reducing is not the same as removing. Chemically when something is reduced it is added elsewhere. Assimilation is not reducing.

Any denitrification method can reduce nitrate. Assimilation removes nothing from the system. Some methods can lower the nitrate level, some can not. It is new for me that removing some nitrate is equal with reducing the level. Maybe for mister Webster but not for me. What if as at the same moment more nitrate is produced as removed? Nitrate production is a continuous process in a closed system. So, while removing nitrate it may be possible that the nitrate level increases or am I wrong again? Not in Websters? Logic thinking. Not so difficult. Not so odd?




Even more so now .
Frist you said:

Reducing some nitrate is not the same as reducing the nitrate level.

Now you say in some twisted semantical argument that removing and reducing are not the same. I have no idea what you mean?

Assimilation removes nothing from the system.



Of course not by itself ,nitrogen assimilation into organic matter( including living tissue ) does however reduce nitrate levels and the organically nitrogen binds a exportable via a number of methods including skimming and GAC .Anaerobic reduction of nitrate removes some N directly but not all of the free N escapes the tank as N2 gas either.

[bertoni]

There are a number of materials called plaster. Calcium sulfate is probably what you mean. I don't know of any practical way to form calcium sulfate without causing precipitation of calcium carbonate as well.

[tmz]

[QUOTE=Belgian Anthias;24470383]2 ppm daily may be a lot for a reef aquarium that is kept at minimal nutrients. Not for mixed reefs with a natural look, with a lot of fish and other nutrient demanding animals, leathers, LPS etc... and fed life food. For fish only tanks and marine aquaculture systems.

natural look ????

2ppm NO3 may be tolerable for many corals. Some sensitive sps don't do very well at that level, IME. they brown up and some experience stn. l I keep a wide variety of corals including some leathers, sps , as well as nps in a very heavily fed system with over 50 fish and maintain NO3 near zero( around 0.2ppm ) with PO4 around 0.02ppm to 0.04pmm.

I also keep some leathers, discoma octorals and others in systems with much higher nitrate and most of them do ok. Some leathers like sinularia and nepthea exhibit much more green colors in the lower NO3 water, though.

Do your actually keep any corals ? If so what types? How are they doing?

[Belgian Anthias]

[QUOTE=Belgian Anthias;24470383]2 ppm daily may be a lot for a reef aquarium that is kept at minimal nutrients. Not for mixed reefs with a natural look, with a lot of fish and other nutrient demanding animals, leathers, LPS etc... and fed life food. For fish only tanks and marine aquaculture systems.

natural look ????

2ppm NO3 may be tolerable for many corals. Some sensitive sps don't do very well at that level, IME. they brown up and some experience stn. l I keep a wide variety of corals including some leathers, sps , as well as nps in a very heavily fed system with over 50 fish and maintain NO3 near zero( around 0.2ppm ) with PO4 around 0.02ppm to 0.04pmm.

I also keep some leathers, discoma octorals and others in systems with much higher nitrate and most of them do ok. Some leathers like sinularia and nepthea exhibit much more green colors in the lower NO3 water, though.

Do your actually keep any corals ? If so what types? How are they doing?

2ppm daily nitrate production! Which means that if nothing is done the level will increase daily with 2ppm.

Peter Wilkins said "One must be crazy" about adding VODKA and vinegar in the last interview he gave before he died in 2008. He was against adding anything which was unnatural and of which the outcome was not predictable.

Most reef aquarium systems used today are bases on the Berlin system, Limiting nutrient input, using live rock, stripping the water with a skimmer, adding calcium. Algae scrubbers, DSB etc. where added to expand the limited possibilities for live support of the Berlin aquarium system. When BADES is added the live support of the system is increased considerable and the nitrogen cycle can be closed by removing the daily nitrate production daily. Every day.

My knowledge of corals is limited to a few species. From those who are kept alive for about two decades and about a few species I would like to keep.
In nature one will rarely find more than 5 different coral species on a square meter of reef.
To keep a small bevy of Anthias which shows its natural behaviour the aquarium must at least have a hight of 150cm and free water depth of +- 80cm from the glass. Just an example for showing what I mean with "a natural look".
We may have a different definition for " normal" and " natural"

Keeping Brittle Stars is one of my projects. Keeping Anthias an other. Corals are kept to provide a natural habitat. A high nutrient demand combined with high water quality. That is where I need a BADESS for.

[Belgian Anthias]

There are a number of materials called plaster. Calcium sulfate is probably what you mean. I don't know of any practical way to form calcium sulfate without causing precipitation of calcium carbonate as well.

Indeed, calcium sulphate. In a reactor filled with calcium carbonate that would not be a problem.
In SLAD systems oyster shell is mixed with elemental sulphur. Precipitation of calcium sulfhate is one of the reasons why the reactors have to be cleaned and backwashed regularly to prevent clogging. This in fresh water ph +- 6.5-7.
Both sulphate and calcium are produced in the reactors.
Calcium hydroxide or kalkwasser can be used for sulphate removal by precipitation. Maybe in a separate reactor where calcium sulphate can precipitate on a filter bed which can easily be removed.

[bertoni]

I agree that calcium hydroxide will precipitate calcium sulfate, but you'll also loose a lot of alkalinity and magnesium. I don't think you'll get selective precipitation, but I might be wrong. The high pH should precipitate a lot of magnesium hydroxide:

http://reefkeeping.com/issues/2005-07/rhf/index.htm#6

[Belgian Anthias]

I agree that calcium hydroxide will precipitate calcium sulfate, but you'll also loose a lot of alkalinity and magnesium. I don't think you'll get selective precipitation, but I might be wrong. The high pH should precipitate a lot of magnesium hydroxide:

http://reefkeeping.com/issues/2005-07/rhf/index.htm#6

Thanks!

[Belgian Anthias]

This invention claims sulphate removal in combination with BADES.
Activ carbon is added to the reactors.

https://books.google.com.tr/patents/US7485229

[bertoni]

That's interesting. It might be interesting to try something similar, although it'd take some lab equipment to determine whether it's working.

[Belgian Anthias]

That's interesting. It might be interesting to try something similar, although it'd take some lab equipment to determine whether it's working.

The invention claims: The sulfur-reducing bacteria grown inside the absolute anaerobic gaps of active carbon are capable of reducing sulfates produced by the autotrophic denitrifying bacteria into hydrogen sulfide. Part of the denitrifying bacteria use hydrogen sulfide as electron donor and re-oxidize it into sulfates.



2CH2O + 2SO4 -2 ⇒ 2HCO3 + H2S CH2O = organics

5S2 + 8NO3 +8H+ ⇒ 5SO4 2- +4N2 +4H2O if enough nitrate is available
This way sulphate can be recycled and each cycle sulphate is reduced by half.

5S2 + 2NO3 + 12H2 ⇒ 5S0 + N2 + 6H2 O when not enough nitrate is available
This way all sulphate is reduced and S recycled.

These are normal reactions within the biofilm
Within the bio-film organics from the bio-film are recycled constantly in there microbiological environment. I doubt these organics can reach the activated carbon. In a healty bio-film on sulphur particles no sulphate reducing bacteria are present.

In the BADES- reactor most organics present in the water column will be mineralized and nitrified as the influent contains +- 5ppm O

When sulphate reduction takes place after all nitrate is reduced and organics are present.

SO4 −2 + H+1 → H2 S +H2 O + chemical energy
(CH2 O)106(NH3)16H3 PO4 + 53 SO4 2− → 53 CO2 + 53 HCO3 − + 53 HS− +16 NH3 + 53 H2 O + H3 PO4

Probably HS must be removed by oxydation outside the reactor.

HS− + 2 O2 → HSO4 −

This way sulphate will not be removed.

I doubt this invention will work the way it is described for a reef aquarium.

Maybe when the activated carbon is placed in a separate reactor in series after the BADES-reactor. I think it will not be possible without adding extra organic carbon. This way the reactor could also be used to provoke phosphate release for BPR ( Biological Phosphate Removal) as the conditions are about the same. No nitrate and enough organics.

[MorganAtlanta]

A BADESSystem gives control to the user over the nitrate removal rate, the daily nitrate removal and the nitrate level. Managed correctly the nitrogen cycle may be closed in a closed aqua-culture system. Once in balance on the by the user desired nitrate level, the BADES system is self-regulating. A BADESSystem is based on the daily to remove nitrate production.



Would you post (or point to) a diagram of a BADESSystem designed for a typical reef aquarium? It would help to visualize what you are talking about.

[Belgian Anthias]

Would you post (or point to) a diagram of a BADESSystem designed for a typical reef aquarium? It would help to visualize what you are talking about.

A 1% BADES- reactor ( 1% of the total volume of the system) is able to keep the nitrate level at +- 1ppm while removing +- 1 ppm nitrate on a daily basis. This means the total volume of the system has to pas true the reactor once daily if the effluent of the reactor is kept at 0 nitrate. When less as 1ppm production has to be removed daily the flow is adjusted accordingly while maintaining the level at 1ppm.
When the daily nitrate production is removed every day, the level is kept steady and the nitrogen cycle is closed within the closed aqua-system.
For a 1000 litre aquarium, 10 litre sulphur is used for BADES in this example.

[MorganAtlanta]

In a BADES system, is the reactor recirculating to give high flow through the media, even if the overall throughput is much lower?

Is calcium media contained in the same reactor?

Is it recommended to pass the effluent through calcium media before returning it to the tank?

A picture might be worth a thousand words here...

[Belgian Anthias]

In a BADES system, is the reactor recirculating to give high flow through the media, even if the overall throughput is much lower?

Yes, but the sulphur is immobilized between two patches to prevent the substrate to move around and avoid to much erosion. Flow is high enough to prevent clogging but not to high to prevent washing out the biofilm. A small circulation pump is plumbed in a closed loop for easy flow regulation. The reactor can be any container that can be closed. Buckets or containers used for food transport have a big lid which makes the reactor easily accessible.


Is calcium media contained in the same reactor?

No, separate reactors of the same volume. Calcium-reactors have to be serviced regularly.(+- every month). We advice two calcium reactors. this way the system stays operational during service.

Is it recommended to pass the effluent through calcium media before returning it to the tank?

Yes. A BASDESSystem contains always a BADES-reactor and a calcium-reactor. The effects of nitrification and denitrification on alkalinity are minimized and a bit calcium is produced.

A picture might be worth a thousand words here...

There is nothing new about a BADESSystem. It is based on the systems as published by Marc Longouet.

http://recifal.fr/chimie-de-laquarium-recifal/
http://mars.reefkeepers.net/USHomePage/USArticles/SulphurDenitrator.htm
http://www.aquarium-portedoree.fr/sites/aquarium-portedoree.fr/files/denitratation1.pdf

In a BADESS fluidized reactors are used instead of column reactors. The volume of the reactor is based on the daily to remove quantity of nitrate and the by the user desired nitrate level. The reactor must be big enough to be able to consume the oxygen entered at the flow needed to remove the daily nitrate production daily.


We have written a dokuwiki called " Makazi Baharini " which contains all information and references from our research. The wiki was at first intended to be for personal use only.
The wiki is written in Dutch. I am occupied to translate the BADESS section in English. The wiki contains a lot of references which are "all rights reserved". I have to ask permission for publication or remove or replace the references before publication. It is the intention that all references used can be consulted. Purchase publication rights is to expensive, sometimes 800$ for one reference. Download one reference may be +- 35$ "All rights reserved". For the moment we are occupied reviewing all references while translating. When finished we will open our wiki for registered users. I hope to finish this work within a few months.

[Belgian Anthias]

T.denitrificans can not grow on elemental sulphur using free oxygen.

T.d. are able to use both forms of RuBisCo, the way enzymes are used to attain carbon from CO2 and building up there cells and membranes. Most bacteria can only use one form. T.d. can only use both ways in anaerobic mode and can grow on sulphur compounds aerobically but when growing on elemental sulphur they need both ways. That is what makes the bacteria very special.

Read the references for the wiki page which are approved and this:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC107408/

The findings are in line with what is experienced in practice. We now know also why!

Some drinking water plants use thiosulphate to induce autotrophe denitrification because of the higher possible nitrate removal rate. Tests have shown a higher sulphate production in correspondence with the nitrate removal rate. This may be because DO is used by T.d. (vacuum degassed water may still contain 0.5ppm to 2ppm DO) instead of nitrate which is wasting thiosulphate and the sulphate production may become problematic for drinking water. When elemental sulphur is used a lot less sulphate is produced.

This is not correct. Thiobacillus denitrificans has the unusual ability of oxidizing sulfur under both aerobic and anoxic (denitrification) conditions. So, it is of interest to concern (sulphate production) whether different sulfur-oxidizing enzyme systems were utilized under different conditions.

T.D. use aerobe RuBisCo form I and anaerobe form II for oxidizing sulphur compounds. Full gnome sequencing has also shown that they are able to oxidise sulphide to sulphate but not to elemental sulphur. Any way, I can conclude that T.d. can not oxidise elemental sulphur in oxic conditions although they can oxidise other sulphur compounds in aerobe conditions. It is the way they use to fix carbon.

[Phenomanul]

The invention claims: The sulfur-reducing bacteria grown inside the absolute anaerobic gaps of active carbon are capable of reducing sulfates produced by the autotrophic denitrifying bacteria into hydrogen sulfide. Part of the denitrifying bacteria use hydrogen sulfide as electron donor and re-oxidize it into sulfates.



2CH2O + 2SO4 -2 ⇒ 2HCO3 + H2S CH2O = organics

5S2 + 8NO3 +8H+ ⇒ 5SO4 2- +4N2 +4H2O if enough nitrate is available
This way sulphate can be recycled and each cycle sulphate is reduced by half.

5S2 + 2NO3 + 12H2 ⇒ 5S0 + N2 + 6H2 O when not enough nitrate is available
This way all sulphate is reduced and S recycled.

These are normal reactions within the biofilm
Within the bio-film organics from the bio-film are recycled constantly in there microbiological environment. I doubt these organics can reach the activated carbon. In a healty bio-film on sulphur particles no sulphate reducing bacteria are present.

In the BADES- reactor most organics present in the water column will be mineralized and nitrified as the influent contains +- 5ppm O

When sulphate reduction takes place after all nitrate is reduced and organics are present.

SO4 −2 + H+1 → H2 S +H2 O + chemical energy
(CH2 O)106(NH3)16H3 PO4 + 53 SO4 2− → 53 CO2 + 53 HCO3 − + 53 HS− +16 NH3 + 53 H2 O + H3 PO4

Probably HS must be removed by oxydation outside the reactor.

HS− + 2 O2 → HSO4 −

This way sulphate will not be removed.

I doubt this invention will work the way it is described for a reef aquarium.

Maybe when the activated carbon is placed in a separate reactor in series after the BADES-reactor. I think it will not be possible without adding extra organic carbon. This way the reactor could also be used to provoke phosphate release for BPR ( Biological Phosphate Removal) as the conditions are about the same. No nitrate and enough organics.

I'm currently in the process of using the sulfur denitrificator in conjuction with active carbon based on one of the linked patent.

[Phenomanul]

Though I have an important question... First a brief description of the system: I have a 210 gallon reef tank (plus a 30 gallon sump and an additional 10 gallons in the piping and other equipment (UV sterilizer, carbon beds, GFO bed, chiller, and the interstitial volume in the Sulfur reactor system). The Sulfur reactor was built by Aquarium Engineering - it is 8" I.D. and about 24" tall. The recirculation rate through the primary sulfur reactor is on the order of 1,000 gph. I do have a second recirculating reactor in series with this one (Skimz NM122) loaded with crushed coral aragonite (Reborn from two Little Fishies along with some magnesium carbonate media) and the circulation rate through that one is about 400 gph. I monitor the ORP in the Sulfur Reactor circulating loop to keep it slightly above zero in order to control my feed rate to the system (using a Sicce 3.5 pump at 9-12 ft of head depending on flow). The normal feed rate to prevent anoxic regimes and the production of H2S has been on the order of 500-600 ml/min.

The question is as follows: If I add 2 gallons of sulfur prills into a 8" reactor chamber and 2.5 gallons of activated carbon (BRS Premium ROX 0.8). should I mix them evenly or load the sulfur media first and then the active carbon afterwards...?

[bertoni]

I would keep the media separate so that they can be replaced as needed, but I have no experience with this approach. If the carbon is mean to adsorb hydrogen sulfide and other compounds, I think it'll need to be replaced at some interval.

[Belgian Anthias]

Though I have an important question... First a brief description of the system: I have a 210 gallon reef tank (plus a 30 gallon sump and an additional 10 gallons in the piping and other equipment (UV sterilizer, carbon beds, GFO bed, chiller, and the interstitial volume in the Sulfur reactor system). The Sulfur reactor was built by Aquarium Engineering - it is 8" I.D. and about 24" tall. The recirculation rate through the primary sulfur reactor is on the order of 1,000 gph. I do have a second recirculating reactor in series with this one (Skimz NM122) loaded with crushed coral aragonite (Reborn from two Little Fishies along with some magnesium carbonate media) and the circulation rate through that one is about 400 gph. I monitor the ORP in the Sulfur Reactor circulating loop to keep it slightly above zero in order to control my feed rate to the system (using a Sicce 3.5 pump at 9-12 ft of head depending on flow). The normal feed rate to prevent anoxic regimes and the production of H2S has been on the order of 500-600 ml/min.

The question is as follows: If I add 2 gallons of sulfur prills into a 8" reactor chamber and 2.5 gallons of activated carbon (BRS Premium ROX 0.8). should I mix them evenly or load the sulfur media first and then the active carbon afterwards...?

I can not answer this. I would contact those who made the claim for the invention.

If I would try it out I would certainly not mix the carbon with the sulphur;

In a BADESS all processes take place within the biofilm on the sulphur pellets as the reactor is not kept anoxic (<0.5ppm DO). In a BADES reactor nitrification and denitrification can take place simultaneously.
At normal operation ( nitrate level < 1ppm NO3-N) the C/N ratio is favorable for mixotrophe denitrification which results in a low sulphate production. Precipitation in the calcium reactors makes that part of the production can be removed . Sulphate production should not be a problem in a normal mixed reef aquarium as only +- 1-2 ppm nitrate has to be removed daily;

[Phenomanul]

I can not answer this. I would contact those who made the claim for the invention.

If I would try it out I would certainly not mix the carbon with the sulphur;

In a BADESS all processes take place within the biofilm on the sulphur pellets as the reactor is not kept anoxic (<0.5ppm DO). In a BADES reactor nitrification and denitrification can take place simultaneously.
At normal operation ( nitrate level < 1ppm NO3-N) the C/N ratio is favorable for mixotrophe denitrification which results in a low sulphate production. Precipitation in the calcium reactors makes that part of the production can be removed . Sulphate production should not be a problem in a normal mixed reef aquarium as only +- 1-2 ppm nitrate has to be removed daily;

So then I would have to procure a 3rd recirculating reactor? First sulfur, then activated carbon, and then the crushed coral (for pH buffering of sulfur reactor effluent)?

[Belgian Anthias]

So then I would have to procure a 3rd recirculating reactor? First sulfur, then activated carbon, and then the crushed coral (for pH buffering of sulfur reactor effluent)?

I would not mix sulphur with the carbon because the carbon has to be replaced regularly.
But for the processes involved I would mix it with the sulphur to avoid all nitrate is removed before the water can reach the carbon. Difficult and unpractical.!?

I never tried this out because I think it can not work in bio-film reactors and the outcome is difficult to predict.

The whole idea is that within the pores of the carbon sulphate reduction takes place and the sulphide is than recycled to SO4 or S. The produced SO4 is recycled again and again, this way reducing the total amount of sulphate. Correct me if wrong.
For this to happen nitrate must be available in anoxic conditions. As it is not available in the pores of the carbon, otherwise sulphate would not be reduced to form sulphide, it must still be available in the seed water, water without dissolved oxygen. The reactor must be kept anoxic?
Sulphur bacteria on the sulphur substrate may use up the nitrate before it can reach the carbon., HS may be produced by sulphate reduction which can not be recycled to SO4 or S because not enough nitrate is available. When a lot of organics become available we may have created a problem. That is a process we must try to avoid in a sulphur denitrator.

This invention may work when high amounts of nitrate are available and a lot of sulphate is produced and the effluent is not kept nitrate free as a safety precaution. In a reef aquarium with only small amounts of nitrate and relative low C/N ratio?
I would not try it out in a live support system.





I

[Belgian Anthias]

using a BADESS we try to avoid sulphate reduction due to lack of nitrate.

In a normal bio-film on sulphur particles sulphate reducing bacteria are not present.(Koing2005)
Most bio-chemical processes take place within the bio-film as the reactor is NOT kept anoxic. The effluent still contains DO!
In the sub layers of the bio-film on the sulphur substrate, which has become an OMZ, nitrate is reduced and sulphur oxidized. When no nitrate is available any more for some bacteria these bacteria starve . They do not try to reduce sulphate. This biomass is then used by heterotrops to produce HS. Than this HS is oxidised to SO4 or S in the middle and lower layers of the bio-film where nitrate is available to deliver the oxygen. By this process nitrate is removed and a lot less sulphate is produced for removing the nitrate as when elemental sulphur is used. This is an ongoing process in a bio-film on sulphur beats and any other bio-film. When +- 30% of the bio-film is occupied reducing nitrate by oxidizing elemental sulphur the same time +-45 % of the bio-film is occupied with recycling the bio-film itself.
+- 15% of the total nitrate may be removed by oxidation of HS. HS can not reach the water column as long as enough nitrate can penetrate the bio-film. One of the reasons why a BADESS is best used for nutrient rich systems wherein a constant supply of nitrate is produced.
When HS would reach the water column the very small amount is easily removed by aeration producing HSO4.

In a BADESS we are talking about very small amounts HS which will easily be oxidized due to the availability of oxygen in the reactor water column.

In anoxic kept sulphur reactors used in marine systems sulphate reduction may produce a lot of HS, to much to recycle. Mismanagement easily turns an anoxic reactor into a HS factory at elevated C/N ratio. Not advisable to be used in a life support system although when used correctly there should be no problems at all.

[Phenomanul]

using a BADESS we try to avoid sulphate reduction due to lack of nitrate.

In a normal bio-film on sulphur particles sulphate reducing bacteria are not present.(Koing2005)
Most bio-chemical processes take place within the bio-film as the reactor is NOT kept anoxic. The effluent still contains DO!
In the sub layers of the bio-film on the sulphur substrate, which has become an OMZ, nitrate is reduced and sulphur oxidized. When no nitrate is available any more for some bacteria these bacteria starve . They do not try to reduce sulphate. This biomass is then used by heterotrops to produce HS. Than this HS is oxidised to SO4 or S in the middle and lower layers of the bio-film where nitrate is available to deliver the oxygen. By this process nitrate is removed and a lot less sulphate is produced for removing the nitrate as when elemental sulphur is used. This is an ongoing process in a bio-film on sulphur beats and any other bio-film. When +- 30% of the bio-film is occupied reducing nitrate by oxidizing elemental sulphur the same time +-45 % of the bio-film is occupied with recycling the bio-film itself.
+- 15% of the total nitrate may be removed by oxidation of HS. HS can not reach the water column as long as enough nitrate can penetrate the bio-film. One of the reasons why a BADESS is best used for nutrient rich systems wherein a constant supply of nitrate is produced.
When HS would reach the water column the very small amount is easily removed by aeration producing HSO4.

In a BADESS we are talking about very small amounts HS which will easily be oxidized due to the availability of oxygen in the reactor water column.

In anoxic kept sulphur reactors used in marine systems sulphate reduction may produce a lot of HS, to much to recycle. Mismanagement easily turns an anoxic reactor into a HS factory at elevated C/N ratio. Not advisable to be used in a life support system although when used correctly there should be no problems at all.


Thank you very much Belgian Anthias... I added 1.8 gallons of sulfur to the reactor but was convinced by your explanations to omit the activated carbon from the load.

I didn't quite add sufficient sulfur to meet the 1% ratio of sulfur to aquarium volume because it seemed like the sulfur prills were very small and had a large amount of surface area to begin with. Also, I want the reactor to be semi-fluidized so that I don't form bio-film plugs with dead bacterial remnants - which meant I needed to provide sufficient disengagement height below the recirculation pump intake nozzle so that the prills would not get sucked into it.

I haven't set connected the reactor to the system simply because I still have to float out the sulfur fines and it's late. I'll get to that tomorrow... (which also means I have to skip a feeding to prevent nitrates from building up faster than desired until the reactor is removing nitrates again...)

[Phenomanul]

Also, I'm using an ORP meter to monitor the reduction potential in the circulation loop as a way of regulating the feed flow. My understanding is that the ORP will hover just above zero when the flow has been optimized to prevent the operation of the system in an anoxic regime.

[Belgian Anthias]

Also, I'm using an ORP meter to monitor the reduction potential in the circulation loop as a way of regulating the feed flow. My understanding is that the ORP will hover just above zero when the flow has been optimized to prevent the operation of the system in an anoxic regime.

ORP does not tell a lot about DO. ORP probes do not react very fast to DO changes and DO readings are not much influenced by DO. http://reefkeeping.com/issues/2003-12/rhf/feature/
In water treatment plants where ORP is used for monitoring the processes the anocic zone ( >0.5ppm DO) is considered to be between 100mV and -100mV. ( batch reactors)


Keeping an anoxic regime in a tube ractor is not the same as in a reactor with internal circulation. In a tube reactor with up flow the oxygen rich water is coming in at the bottom and as the water moves up oxygen is consumed to become an anoxic zone on top. In a reactor with internal circulation top water is mixed with incoming water. When this reactor is kept at anoxic ORP reading the entire reactor may become anoxic as a lot less oxygen can be entered to become the same ORP reading. Less oxygen means less influent and less nitrate which may cause unwanted processes.
Such a reactor may have very little potential when a low nitrate level is desired.

In a BADESS ORP monitoring does not tell us a lot about the DO but can help to prevent the reactor to become anoxic intendedly.

[Belgian Anthias]

Thank you very much Belgian Anthias... I added 1.8 gallons of sulfur to the reactor but was convinced by your explanations to omit the activated carbon from the load.

I didn't quite add sufficient sulfur to meet the 1% ratio of sulfur to aquarium volume because it seemed like the sulfur prills were very small and had a large amount of surface area to begin with. Also, I want the reactor to be semi-fluidized so that I don't form bio-film plugs with dead bacterial remnants - which meant I needed to provide sufficient disengagement height below the recirculation pump intake nozzle so that the prills would not get sucked into it.

I haven't set connected the reactor to the system simply because I still have to float out the sulfur fines and it's late. I'll get to that tomorrow... (which also means I have to skip a feeding to prevent nitrates from building up faster than desired until the reactor is removing nitrates again...)

One can put the sulphur between two filter patches. This way the sulphur will not swirl around and internal flow can not provoke to much erosion. The sulphur may not be squeezed between the patches.
I do not know what you mean with semi-fluidized.
At a normal reef aquarium C/N ratio bio-film plugs will seldom occur when internal flow is high enough. To high is also not good as parts of the the bio-film may come loose. When the circulation pump is plumbed in with a closed loop it can be used for back washing the reactors. Light may not reach the sulphur.

[Belgian Anthias]

Can ORP be used for monitoring a BADES reactor?.

What are the ORP limits? Difficult to say. ORP reading is very senstive for pH (H+) changes. A drop of 1pH unit will increase ORP with +- 60 mv. It is important that the ORP reading is taken after the calcium reactors to become a more reliable reading.
During normal operation pH may drop to +- 7 pH in the effluent of the sulphur reactor, ORP may increase with +- 75 mv. When a lot of nitrate is removed at low flow, as during lowering the nitrate level, pH in the reactor may drop till +-pH 6= ORP reading increase +- 130mv.
ORP +- 0mv at PH 6 = ORP - 130mv at pH 8.2;
When a high nitrate level is present a lot more oxygen is enclosed in the nitrate as there is DO. ORP will not tell much about DO present in the water.
An expensive ORP probe with good auto pH correction is a must when ORP is used for feed flow regulation. The ORP probe must be calibrated regularly.

ORP reading and control is often used as a safety measure when anoxic (>0.5ppmDO) kept sulphur reactors are used to prevent sulphate reduction. I doubt the safety of this measure.

My opinion ORP is not very reliable for managing a BADES reactor, a reason for not using ORP for this purpose.
As a BADES-reactor is NOT kept anoxic and a continues nitrate source is provided, measures to prevent sulphate reduction are not a concern.

In a BADESS H+ is produced by nitrification and denitrification processes within the BADES-reactors which is removed in the calcium reactors. pH monitoring will tell me a lot more about the functioning of the system.

[Phenomanul]

Can ORP be used for monitoring a BADES reactor?.

What are the ORP limits? Difficult to say. ORP reading is very senstive for pH (H+) changes. A drop of 1pH unit will increase ORP with +- 60 mv. It is important that the ORP reading is taken after the calcium reactors to become a more reliable reading.
During normal operation pH may drop to +- 7 pH in the effluent of the sulphur reactor, ORP may increase with +- 75 mv. When a lot of nitrate is removed at low flow, as during lowering the nitrate level, pH in the reactor may drop till +-pH 6= ORP reading increase +- 130mv.
ORP +- 0mv at PH 6 = ORP - 130mv at pH 8.2;
When a high nitrate level is present a lot more oxygen is enclosed in the nitrate as there is DO. ORP will not tell much about DO present in the water.
An expensive ORP probe with good auto pH correction is a must when ORP is used for feed flow regulation. The ORP probe must be calibrated regularly.

ORP reading and control is often used as a safety measure when anoxic (>0.5ppmDO) kept sulphur reactors are used to prevent sulphate reduction. I doubt the safety of this measure.

My opinion ORP is not very reliable for managing a BADES reactor, a reason for not using ORP for this purpose.
As a BADES-reactor is NOT kept anoxic and a continues nitrate source is provided, measures to prevent sulphate reduction are not a concern.

In a BADESS H+ is produced by nitrification and denitrification processes within the BADES-reactors which is removed in the calcium reactors. pH monitoring will tell me a lot more about the functioning of the system.


Thanks again... after the initial reduction in system nitrates from 10 ppm down to <2 ppm the pH has stabilized (but nitrate concentration hit that 2 ppm wall). Seems I have to add more sulfur to get it to remove more nitrates to maintain 0 ppm.

[Belgian Anthias]

Thanks again... after the initial reduction in system nitrates from 10 ppm down to <2 ppm the pH has stabilized (but nitrate concentration hit that 2 ppm wall). Seems I have to add more sulfur to get it to remove more nitrates to maintain 0 ppm.

Daily flow X nitrate level = daily nitrate removal rate (if effluent is kept at O nitrate)
When the nitrate level decreases flow must increase to remove the same amount of nitrate.
It is enough to remove the daily nitrate production daily to keep the level steady, a bit more fore the level to be lowered.

It is possible that the reactor can not remove enough nitrate to lower the level below 2ppm because the daily nitrate removal rate equals the daily production.
Increasing the flow a bit will enter more nitrate and more DO ( if the flow was previously not adjusted to the nitrate level, this must be done with small increments.)
Wait after each flow correction for the reactor to be able to consume the increased DO entered.
To be able to lower the level from 2ppm to 1ppm the flow must be doubled. This means that the amount of oxygen entered is doubled also.

When the daily flow is known the daily nitrate production can be calculated. I need this info to determine if more sulphur must be added to solve this. Is the level stabilized at 2ppm NO3-N or 2ppm NO3 ? ( test kit)

When the reactor is kept anoxic it may not be possible to increase the flow to enter more nitrate as due to the increased DO the reactor can not be kept anoxic any more. In this case adding more sulphur will certainly not solve the problem.

[kadaytar]

Hi Belgian Anthias, thanks for taking your time and sharing all this info about BADES system. Maybe you have already answered some of them but I have some questions.

- Is a recirculating pump necessary on the reactor holding sulfur media? What are the benefits of recirculating pump?
- Do you use a protein skimmer ? Can BADES system keep nitrates undetectable in a skimmerless system?
- Can you post some pictures of your reactor and your display tank or any other mixed reef tank running with BADES system for more than 3-4 years?

[Belgian Anthias]

[QUOTE=kadaytar;24725474]Hi Belgian Anthias, thanks for taking your time and sharing all this info about BADES system. Maybe you have already answered some of them but I have some questions.

- Is a recirculating pump necessary on the reactor holding sulfur media? What are the benefits of recirculating pump?
For a BADES-bioreactor a recirculting pump is used. Prevents clogging and tunneling in tube reactors. All types of containers can be used as a reactor. Treated water water is mixed with the influent creating a more stable environment, Erosion of the biofilm can be managed. Precautions are taken for the media not to move around.
- Do you use a protein skimmer ? Can BADES system keep nitrates undetectable in a skimmerless system?
A bio-skimmer, the air flows first true an oyster shell bed, used to aerate the outflow and stabilise PH. Undetectable? There is always nitrate produced in a healthy system. A BADESS needs a nitrate source to work fine. As the aquarium bio-system needs nitrogen. The system can keep the nitrate level below 1ppm or lower in any closed system. One can make it as big as desired as long as enough nitrate is produced in the closed system.
- Can you post some pictures of your reactor and your display tank or any other mixed reef tank running with BADES system for more than 3-4 years?
The best known example is the system installed by Hignette in the Grand Aquarium de Saint Malo in 1996 with 450 kg sulphur. It was still in use in 2010 and probably still is.(HIGNETTE, Michel, Benoit LAMORT, Marc LANGOUET, Sébastien LEROY, en Guy MARTIN. “Elimination des nitrates par filtration biologique autotrophe sur soufre en aquariologie marine”. Mémoire Institut Océanographique Paul Ricard, 1997, 7–13. ) Marc Longouet tested it for over 6 years in reef aquaria some systems without water changes for about 2 years. http://recifal.fr/chimie-de-laquarium-recifal/ More recently a BADES was installed at the aquarium of Rochelle in 2007 (http://www.aquarium-portedoree.fr/sites/aquarium-portedoree.fr/files/denitratation_rochelle.pdf) and the Grand Bassin Marin de l'Aquarium du Québec 2010 (MARIE-CHRISTINE SIMARD, 2010 ).
A BADESSystem is not more than a BADES bio film reactor used in a closed system as described. A container filled with elemental sulphur used as a biofilter.

[ /QUOTE]

[kadaytar]

Thanks for the answers. I think 1 ppm is not detectable with many of the test kits used in the hobby that's why I said undetectable.

Actually I don't have any problem with nitrates. I use Salifert test kit and the color of sample water tested does not change. So I consider nitrate level is under 2 ppm. The reason I want to give BADES system a try is to go with skimmerless to be able to increase live plankton population in order to keep some non photosynthetic corals that I like.

Can you provide some more information about bio-skimmer and its design? Is the air provided by an air pump or a pump with an air intake? Do you feed it with the effluent from calcium reactor?

Do you mean the second reactor filled with calcium carbonate media fed by the effluent of the sulfur holding reactor as calcium reactor? We need to adjust CO2 injection and flow amount to keep calcium and Kh stable at desired levels while keeping the pH inside around 6,2-6,3 when we use a Ca reactor. How can you adjust the pH and flow rate going in the second reactor?

What is the ideal grain size of sulfur media ?

[Belgian Anthias]

Thanks for the answers. I think 1 ppm is not detectable with many of the test kits used in the hobby that's why I said undetectable.

Actually I don't have any problem with nitrates. I use Salifert test kit and the color of sample water tested does not change. So I consider nitrate level is under 2 ppm. The reason I want to give BADES system a try is to go with skimmerless to be able to increase live plankton population in order to keep some non photosynthetic corals that I like.

Can you provide some more information about bio-skimmer and its design? Is the air provided by an air pump or a pump with an air intake? Do you feed it with the effluent from calcium reactor?

Do you mean the second reactor filled with calcium carbonate media fed by the effluent of the sulfur holding reactor as calcium reactor? We need to adjust CO2 injection and flow amount to keep calcium and Kh stable at desired levels while keeping the pH inside around 6,2-6,3 when we use a Ca reactor. How can you adjust the pH and flow rate going in the second reactor?

What is the ideal grain size of sulfur media ?

In a Berlin system the main function of a skimmer is to prevent mineralization. In a BADESS a skimmer is not necessary for that purpose. No need for aggressively stripping the water.
A bio-skimmer is a skimmer filled partially with any media, sand or oyster shell, where bacteria can grow. Air from an air pump or a venturi is passed first true the media. The main purpose is to aerate the water, stabilize PH by removing produced and/or added CO2, remove any nitrite or HS left over. The skimmer part to remove the by-products of bacterial activity of which a lot are poisonous but are skim-able and also +- 50% of the bacteria population in the water will be removed.( this way also removing some assimilated phosphate) The outflow of the calciumreactor which is placed after the BADES bioreactor is passed true the bio- skimmer.
Bio-skimmers are not common in the aquarium trade but are commercialized for aquaculture purposes which are in most cases to big for an aquarium system.

Standard counter current skimmers can be used. They can also be transformed into a bio-skimmer.

The sulphur we use is +- 4mm x 2 mm
photo: http://www.baharini.eu/baharini/doku.php?id=makazi:chemie:zwavel

The information and research used for the development of a BADESS can be consulted, only in Dutch for the moment but most references used are in English,some in French. http://www.baharini.eu/baharini/doku.php?id=badess:theorie. Can and may be translated into most languages.

[bertoni]

Another important function of a skimmer is oxygenation. They can save a tank from a number of problems, including spawning events and die-offs. They also can remove allelopathic compounds and keep the water clearer. I'd keep a skimmer running in any larger tank, personally.