Is it necessary to add phosphate during alcohol dosing?

[Ontheway]

Hello,

I read zero phosphates and high (around 50) nitrates.

Simple question,
Should I add phosphates (have Seachem one) during (or before, or after) dosing of ethyl-alcohol, to support bacteria development?

[incognitus]

I had to do so. Actually I got rid of 0.5 phosphate with ethyl-alcohol.

[Ontheway]

So it works. I will try it with a small dosage. Hope it helps to get rid of nitrates.

[bertoni]

Your tank might need a bit of phosphate. Trying a small amount should be safe enough. I'd watch the animals carefully, though.

[BrentH]

Originally Posted by Ontheway

So it works. I will try it with a small dosage. Hope it helps to get rid of nitrates.

I have the same exact problem is the sea chem phosphurus safe to add to reef ? Anyone done it in about to order some

[BrentH]

I have learned that u do need some po4 to bring down the n03 there's somewhat of a balancing act I've been see a lot lately were people are having there po4 low instead of there n03 and it seems it is usually the other way around ?

[bertoni]

Tanks with no phosphate and a lot of nitrate and vice versa both seem fairly common.

[Ontheway]

Waiting for phosphate cargo. What I am wondering is, should I add phos before alcohol, or with alcohol, or after..? Or, no difference ? Things I read about organic phos and other phos types confused me. If the seachem phos. content can be used directly (without waiting it to be converted to some other phos form by reactions or by some bacteria), we can add it with alcohol or after, if this phos needs some time to become usable, it may be better to add it prior to alcohol.

Is it a good idea to stop skimmer for an hour or so, during phos/alcohol addition?

[BrentH]

I would not turn off skimmer and I think it wouldn't really matter when phosphurus is dosed I'm going to go really slow. The stuff is made for planted freshwater tanks hope that doesn't matter ?

[hogfanreefer]

I had the same issue but mine was due to aggressie GFO use since I started. All I had to do was stop GFO. Phosphate has risen to 0.024. Wonder when I should add back the GFO?

[Ontheway]

How could you measure 0.024 value? I remember sth like 0.01 is enough for reefs, not sure though.

[bertoni]

The generally recommended upper limit for phosphate is 0.03 mg/L:

http://www.reefkeeping.com/issues/2004-05/rhf/index.htm

Our hobbyist equipment is not very precise at levels in that range, ±0.02 mg/L or so being the best claim I've heard. When the level gets low, watching the animals is more important than the test results.

[tmz]

IME, when starting organic carbon dosing ( vodka vinegar ,etc) with high nitrate levels, it can take months for nitrates to fall significantly.
The effects on phosphate reduction have been much faster at the start.

While, the facultative heterotrophic bacteria involved assimilate nitrogen and phosphate, it takes time for them to dent a high starting baseline of nitrate in some systems ;perhaps it just takes longer for the anaerobic side of the nitrate reduction to occur .

Excesssive use of GFO or other removers during this process can contribute to an imbalance and potentially a phosphate deficiency particularly in a tank that is not fed well. Without GFO or another remover ,it would be a rare occurence .IMO/ It takes very little phosphate vs nitrogen to keep a balance going.

In theory, adding phosphate may eocourage more bacterial acitivity and more nitrogen assimialtion and/or anerobic nitrate reduction.However, extra phosphate in a high nitrate conditions may just increase nuisance algae with minimal efect on nitrogen levels.

I prefer to reduce high nitrate via water changes or a denitrator before starting to dose organic carbon . It's easier to get to a maintenance dose that way .

FWIW, five plus years into vodka and vinegar dosing , NO3 is .5ppm per Salifert with PO4 0.02ppm to 004 ppm ( per hanah 713 colorimeter) consistently . I have not used gfo in over a year ; do use GAC ; feed heavily ;and, have never dosed phosphate directly.

[Ontheway]

Originally Posted by tmz

feed heavily ;and, have never dosed phosphate directly.

I think this explains why you dont need to apply extra phosphate, I am afraiding of feeding heavily because 1st, do not have enough organisms to comsume it, 2nd, I already have high nitrates, do not want to increase it by feeding.

It seems not much people dosed phosphate in order to help bacteria, first hand.

[tmz]

There is not much anecdotal reporting on direct PO4 dosing it. Usually folks esperiencing paling corals with zero PO4 readings stop GFO or other remover applications and feed a bit more with success.

[Ontheway]

Thanks Tom, I will try very small amount and see if it makes any difference.

[tmz]

You are welcome.

Let us know the outcomes.

[Ontheway]

I will share the results, but first let me make some calculations;

The upper limit for aquarium is 0.01 ppm, which means 0.01 mg/L.

If I want to add half of this limit value, I should add 0.005 mg per Liter, makes 5 mg per 1000 Liters, since I have 350 L water in circulation, I need to add one-third of 5 mg, translates to 1.6 mg or 1.6 ml.

Of course, this is assuming seachem phosphate is %99 percent or more pure.

Just found a page @ foster&smith says,

----------------
Expert: The beginner dose raises phosphorus by 0.05 mg/L (0.15 mg/L phosphate). The ideal phosphate level will vary, but generally ranges from 0.15-1.0 mg/L. Use Seachem's MultiTest: Phosphate test kit (#901377) to monitor phosphate levels. To target a specific phosphate increase, dose according to the following formula: 0.8vp=m, where v= volume of tank in gallons*, p=desired phosphate increase and m=volume of product to use in mL. For example to raise 20 gallons* to 0.1 mg/L phosphate you would use: 0.8*20*0.1=1.6 mL.

-----------
Guaranteed Analysis
Available Phosphate (P2O5)
0.3%
Soluble Potassium (K2O)
0.2%
-----------
Derived from: Potassium Phosphate.
-------------------------

According to the formula given above, If I want a 0.005 ppm increase,
0.8*90*0.005= 0.36 ml


Now, do either of these correct?

[tmz]

I'm not familiar with those calculations. Your interpretation seems correct.

The limits Seachem sets are for a freshwater planted tank. Reef tanks work well( in terms of coral vibrancy and limited nuisance algae) with PO4 from 0.01 up to 0.05 ppm IME. Some run them successfully at higher levels.

The fundamental question is whether a PO4 deficiency is limiting nitrogen reduction ,spedifically the NO3 . It might but there are lot's of other possibilities, a lack of anaerobic acitivity ,iron or potassium for example.

How much organic carbon are you dosing ,btw?

[Ontheway]

I am currently dosing 0.5 ml pure etoh, everyday, for four days. Planning to increase it to 0.7 first and a few days later, 1ml. And increase according to.no3 levels measured.

[BrentH]

I an the same don't want to raise no3 by adding extra food to raise po4 so I ordered some as well just incAse it was somewhat cheap I haven't received it yet or added it would ....but for the first time I have a lower no3 reading finally while still having a po4 reading of 0.00 on my Hanna so like I thinkTom said that u don't need very much phosphates present for the bacteria to work

[Ontheway]

BrentH, do you dose alcohol, and if yes, can you please say how much?

[BrentH]

I don't I use the prodibio products biodigest and biotim I add it weekly ....alternating the biodigest(bacteria) and the Biotim (carbon source) I be been useing these products for about 2 months now I was also running gfo up until about 3 weeks ago ..I have a 500 gallon tank about 650 volume ... And a lot if fish and corals

[Ontheway]

Then my situation is different then yours. A lot of coral means you already have organisms help on nitrate reduction. I don't believe you will experience difficulties to reduce nitrates with regular methods.

[Piper27]

I have been having trouble getting nitrates to start dropping with vodka and vinegar. I have got it down to 5 by weekly waterchanges. I am up to 17ml vodka and 80ml of vinegar a day on my 250 gallon system. I noticed I can't get any color on my saliferts phosphate test since starting the dosing. I may try a little phosphate to see if the nitrate drops, or to see if it will register on the test kit. They phos was at .05 to .1 before the carbon dosing. I have around 40 fish and feed like crazy. I try to feed as much as I have time to.