Method to improve biological nitrate reduction?

[blasterman789]

Was at the LFS store the other day......noted the typical tanks of bulk 'Live Rock'.

I then teased the manager about it being Live Rock, but they had no fish in the tank. This, in my opinion really reduces the bacteria load. It's better than dry rock, but might still have to ramp up when put under biologic load. A lot of LFS put fish nobody wants in their LR tanks just for this reason; big damsels, etc.

Then, likely due to too many cans of Monster that afternoon the bug zapper above my brain went off. Why doesn't the same apply for nitrogen reducing bacteria? Those buggers as we know take a much longer time to establish and are more fussy about their conditions (lower water flow, etc).

Take a bucket of tank water, fill it full of LR or chunks, give it just enough circulation so there aren't dead spots (we don't want hydrogen sulfide), and then seed that sucker with lots of potassium nitrate. Keep the levels screaming high at 100ppm. Think this would establish nitrogen reducers better than in a tank?

[Breadman03]

I don’t know, but I’d suggest searching for “sulfur denitrator” and “Donovan’s nitrate destroyer.” You’ll probably find a lot of useful info.

[blasterman789]

I don't have a nitrate problem I'm trying to solve with a gadget. I'm trying to discuss ways of improving nitrate reduction in-tank where it should be, and/or speed up the development of nitrogen reducing bacteria without waiting months/years.

[Scrubber_steve]

I don't have a nitrate problem I'm trying to solve with a gadget. I'm trying to discuss ways of improving nitrate reduction in-tank where it should be, and/or speed up the development of nitrogen reducing bacteria without waiting months/years.

Well there's nitrifying bacteria (oxygen loving) which converts ammonia/ammonium to nitrite & then to nitrate. Then there is de-nitrifying bacteria, which exist in an anoxic environment (very low oxygen) which reduce nitrate to nitrogen gas. Then there is bacteria that exist in anerobic environments (no oxygen) that convert nitrate back to nitrite & ammonia.

Then there is algae, as in scrubber or refugium, that remove ammonia/ammonium without converting it to nitrite/ nitrate.

[Daddi0]

Just dose vinegar

[mcgyvr]

I think you are making an assumption that the higher the nitrate levels the faster the development/growth of de-nitrifying bacteria..
I'm not sure thats the case but rather the time in which the anoxic environments are formed and the amount of them...

[blasterman789]

I think you are making an assumption that the higher the nitrate levels the faster the development/growth of de-nitrifying bacteria..
I'm not sure thats the case but rather the time in which the anoxic environments are formed and the amount of them...

Exactly...and since new tanks that are properly maintained take months and months to even establish elevated nitrate levels (unless you buy really good LR from a high bio load tank) this cuts that time frame because it provides free nitrogen sooner. Like you said though it's theoretical.

I've set up a *lot* of tanks in my 30 years of reefing and the only way I've consistently found to speed up the post cycling stability phase is to add some potassium nitrate right at the beginning. Seems to cut a couple months off getting to the stability phase where you're done with nuisance algae / cyano / diatom blooms. Good luck adding SPS or more sensitive LPS during this phase.

Carbon dosing fuels nitrogen reduction. No proof it encourages actual bacterial growth I've seen. For the second time (in english) I'm not trying to improve nitrate reduction. I'm trying to speed up and get newer tanks to their stability point so the nitrogen reducing bacteria can quicker compete with post cycling outbreaks.

[Big E]

Carbon dosing fuels nitrogen reduction. No proof it encourages actual bacterial growth I've seen.

Sure it does, it's the basis of any of the bacterial nutrient reduction systems and why people use them.

There's plenty of of commercial bottled bacteria that can help speed this up. MicroBater 7 comes to mind off the top of my head. In this case you are physically adding the bacteria that hasn't naturally established itself.

[hottuna]

Gonna bring back an old school concept here and wait for all the gasps !....plenum/NNR
hook up a tank with a jaubert plenum...add about 4-5" of florida crushed coral..plumb into main tank ...and feed tank water through the plenum tank and back into the main display..
takes up alot of real estate, I know ...but it works...another idea is to just run 6" depth of florida crushed coral in a tank without plenum and do the same thing...I prefer the plenum..I have used systems like this for over 30yrs..time proven and always work for me...FWIW

[reefgeezer]

... being Live Rock, but they had no fish in the tank. This, in my opinion really reduces the bacteria load...

I'd be surprised if the live rock sits long enough at an LFS to completely cure. IMO, there's probably more than enough die off in those bulk live rock tanks to provide pretty high levels of nitrate, not to mention ammonia, nitrite, and phosphate.

... Take a bucket of tank water, fill it full of LR or chunks, give it just enough circulation so there aren't dead spots (we don't want hydrogen sulfide), and then seed that sucker with lots of potassium nitrate. Keep the levels screaming high at 100ppm. Think this would establish nitrogen reducers better than in a tank?

Putting dry rock in ASW in the manner mentioned above with Lanthanum Chloride to free bound phosphate is a common practice. Maybe adding a nitrogen compound also (ammonia, potassium nitrate, etc.) during that process would serve the purpose you are seeking. I'm not sure of the chemistry involved though. I would also point out that some carbon needs to be present for the process to work.

[Tripod1404]

Carbon dosing fuels nitrogen reduction. No proof it encourages actual bacterial growth I've seen.

The reality is the opposite. It fuels bacterial growth, there is anecdotal evidence that it actually enhance the rate of nitrogen reduction.

That is why carbon dosing require good skimmer and it can cause bacterial blooms or white slime if done wrong. And also it is the reason why nitrate amounts can raise if you suddenly stop carbon dosing. If there was major nitrate to nitrogen conversion, sudden increases in nitrate in response to stopping carbon dosing would not be possible.

[djbon]

I am on carbon dosing in a controlled environment for years and decided it might be okay running my reef tank without skimmer. After many months running without one, and still doing carbon dosing until today, I know bacteria is the answer to my nutrients management. It's easy, fully predicted and most importantly it's free. I like the concept of nutrient recycling method very much.

[Horace]

I am on carbon dosing in a controlled environment for years and decided it might be okay running my reef tank without skimmer. After many months running without one, and still doing carbon dosing until today, I know bacteria is the answer to my nutrients management. It's easy, fully predicted and most importantly it's free. I like the concept of nutrient recycling method very much.

If you are not using a skimmer, or some way to export the excess bacteria, I am going to have to disagree with you here. You may have built up a large colony of bacteria which sucked up those nutrients, but I dont think that is sustainable long term. I think eventually you will need to export that bacteria, or risk all those nutrients being dumped back into the system.

The idea is that the bacteria consume the nutrients and are exported via skimming. If you dont remove the bacteria/nutrients, they are just building up.

[reefgeezer]

...The idea is that the bacteria consume the nutrients and are exported via skimming. If you dont remove the bacteria/nutrients, they are just building up.

The organics and the bacteria resulting from carbon dosing can be handled by mechanisms other than skimming in very mature systems. The process is more of a recycling or binding process rather than exporting. It's not my thing, but it is a viable and possibly more advanced option. I don't have the patience required.

[djbon]

+1 for reefgeezer. I won't recommend a complete recycling method in a less than 2 years tank. Mine is more than 4, all live rocks and sands are freshly harvested from the ocean. I remember correctly that my cycling period only lasted 3 days, so I know the substrate is full with nature's goodness. After many months running without skimmer, without any mechanical filters etc (only GAC), my nitrate is still below 5ppm, PO4 less than 0.05ppm. I have to admit that I do have a small algae through (4" diameter PVC pipe cut into half, end capped on both side) but I don't throw the harvested algae, I fed it to my fishes. So far my tank is doing great.

[reefgeezer]

... After many months running without skimmer, without any mechanical filters etc (only GAC), my nitrate is still below 5ppm, PO4 less than 0.05ppm.

Nice tank. Those big softies you have are an example of organisms that bind nutrients in their body mass. I see why you have GAC in your system.

[djbon]

Thanks reefgeezer. Yup, occasionally an overgrown corals will be donated to fellow reefers. For a standard 75g tank, I don't have much space to let them grow so big, so pruning is necessary. GAC helps a lot, I have live pacific oysters in the sump and cryptic zone as filters. So far it does the job quite good but the best thing about live oysters is "oyster feast" for corals.

[outy]

I'm trying to discuss ways of improving nitrate reduction in-tank where it should be, and/or speed up the development of nitrogen reducing bacteria without waiting months/years.

That's not going to do it, its just making live rock. The bacteria populations will stabilize once introduced into a new tank. You wont gain any nitrate reduction.

Decades ago it was common to load a tank up with LR for nitrate reduction, wasn't it called the Berlin method? Anyone not that great of an idea.


Today we have many better methods of nutrient export. I prefer a DSB knowing it has a limited lifespan, before I have to do a complete tear down.

[shellsea]

Gonna bring back an old school concept here and wait for all the gasps !....plenum/NNR
hook up a tank with a jaubert plenum...add about 4-5" of florida crushed coral..plumb into main tank ...and feed tank water through the plenum tank and back into the main display..
takes up alot of real estate, I know ...but it works...another idea is to just run 6" depth of florida crushed coral in a tank without plenum and do the same thing...I prefer the plenum..I have used systems like this for over 30yrs..time proven and always work for me...FWIW

hottuna - I too am old school and ran a Jaubert plenum style tank 30 years ago. Got away from it as the hobby changed. As i recall the scary thing about the plenum or deep sand beds in general is the possibility of disruption in the bed causing release of a bunch of nasties. You have not had that happen?

[Michael Hoaster]

Referring back to blasterman789's original post-it makes sense to me. Heavily load a vessel of new live rock (and why not add sand too?), with nitrate, and Mother Nature should respond with higher nitrate processing capacity. It should be easily testable with a couple of small tanks. If it works, you've just advanced the hobby! It's wacky ideas like this that disrupt the status quo. Love it!

[djbon]

There is nothing new about live rocks capability to process nutrients as good as other methods. I would say live rocks loaded with bacteria and other stuffs (good one off course) works much better due to the fact that they are self regulating without much intervention from us. I have been running mine in such manner (no WC, without skimmer, mechanical filters, GFO or other chemical absorbent) for years with no major issue.

[hottuna]

hottuna - I too am old school and ran a Jaubert plenum style tank 30 years ago. Got away from it as the hobby changed. As i recall the scary thing about the plenum or deep sand beds in general is the possibility of disruption in the bed causing release of a bunch of nasties. You have not had that happen?

No shellsea,,,that is one of the plenum "fallacies" ...set up properly and left alone a plenum will reduce nitrate for yrs...a second screen layer about 1 inch below the top of the sand bed prevents burrowing and disturbing the bed...

other than that - just leave it alone and let it do it's thing....

[PeteStarks]

I have been having pretty good luck with a DIY algae scrubber and a bio pellet reactor. I have spent 10 years chasing fads and those 2 things have been the only ones to actually stick and improve my tank. I'm not saying that there will never be a better alternative, but those 2 solutions check a ton of boxes for most reef tanks.

[Maivortex]

Good luck buying potassium nitrate. Sodium nitrate would be easier but when you add this rock from a bucket into a system with high flow, it will have due off. Also there are toxicity limkts, 100 ppm nitrate may kill nitrate reducing bacteria......