Vinegar Dosing question

[Nanook]

I started dosing vinegar on my 470 gallon reef with 100 gallons in the sump 16 days ago. I started at a higher dose than the chart said to speed up the process, I'm currently at 70cc/day. How long does it typically take to see reduction in nitrate? I'm currently close to 30ppm.

Of note, I have 45 fish and feed heavily.

 

[mcgyvr]

Can be as little as a few weeks to never.. many variables involved..

 

[Dan_P]

Can be as little as a few weeks to never.. many variables involved..

This is a very concise summary of my reading on the subject. Be aware that the standard dosing table has been incorrectly scaled since inception. Everyone following this table has very likely increased the dosage too slowly and likely quit too soon. This might account for some or all the instances where no reduction in nitrates was observed.

Phosphate limitation is another concept in the forum discussions. It goes something like "œif phosphates are too low, heterotrophic bacteria cannot proliferate and consume - assimilate - nitrate". I observed this once on a small scale experiment.

Another angle never discussed is that the bacteria targeted for carbon dosing and consumption of nitrate are also likely to be competing with other microorganisms for ammonia. I believe once the daily ammonia production is consumed, only then is the nitrate consumed. This notion would account for delays in nitrate consumption. For example, systems that are not heavily fed would respond more quickly to carbon dosing where as systems heavily fed and producing more ammonia per hour would require more carbon dosed, and more bacterial growth, before nitrate reduction was observed.

So, as Jonathan has said, "œevery system is different". You will have to feel your way through the dosing process as to how much carbon is needed to achieve your nitrate reduction goal.

 

[mcgyvr]

Be aware that the standard dosing table has been incorrectly scaled since inception.

Isn't the site that has that table under ReefCentral control?
If so lets get it fixed..
I'd be happy to recreate such a simple spreadsheet if needed if someone wants to spit out the correct formula

Nanooks a mod.. tag.. hes it..

Or is that one of those "thou dost not disturb this holy work" things that?
I know Randy is not active here anymore but can't see how it would mind it being corrected if its wrong.. He is still easily reachable for comment..

 

[bertoni]

If you create a nicer table, I can post it. I have been trying to work up some html skills, but they currently are lacking.

I agree that tanks have a highly variable response to carbon dosing. I'd give it a few weeks and least, and then up the dose, as long as the tank doesn't show signs of bacterial slime or cloudy water.

 

[tmz]

How much are you dosing? Each tank is different as Jon
noted but FWIW, 60 ml of 5% acetic acid vinegar plus 36 mil of vodka( approximately equivalent in carbon content to an additional 288ml of vinegar) per day maintains low NO3 and PO4 in my 700 gallon system and has for nearly a decade. I did amp up to that level over a month or so back when I started. Be sure to dose the vinegar slowly since it will cause a precipitous time limited pH drop when large amounts are dosed at once.

It can take a month or months to put a dent in the 30 ppm nitrates ,since ,as Dan noted ,the heterotrophic bacteria are fed in part by carbon dosing take ammonia for nitrogen preferentially in a one step process that does not let the ammonia go to nitrate, in effect cutting of the nitrate input from foods etc; they also take some nitrate but the effect on a standing pool of it are slower. When I started I reduced the nitrate to less than 5ppm with a diy sulfur denitrator before starting the carbon dosing .

 

[Nanook]

I went up to 100cc/day the day after starting this thread, still feeding 45 Fish generously. Nitrate is 26 on Lamotte, phosphate with GFO is .07.

I’m on a dosing pump that adds a few times a day, still seeing lots of green film on glass every couple days.

 

[tmz]

For the 570 gallons you can probably can go to 200cc vinegar or so over the next few weeks or 12 or so ml of vodka plus the 100 ml current dose.

If you see bacterial slime or snotty material back off a bit. Otherwise I'd just hang at 200 for a few weeks and see how things go before tweking that up or down.

Good luck

 

[Daddi0]

My reef is approx. 120 gallons and it gets approx. 1ml of vinegar per gallon of tank volume per day. So 120ml of vinegar a day and I have a manageable amount of bacteria and the tank looks great! With a system that is approx. 500 gallons (volume minus rocks) It would seem that you are at the low end of what you can safely dose. Excess bacteria wont hurt corals (the corals and sponges may actually feed on it) The only downside is that it can be unsightly and could deplete oxygen levels. I used a ph tester to keep an eye on the oxygen.
16 days is not a lot of time when you consider that you have to establish a bacterial colony and skim out the bacteria. The larger the colony, the more reduction you will get.
Cheers! Mark

 

[Dan_P]

I started dosing vinegar on my 470 gallon reef with 100 gallons in the sump 16 days ago. I started at a higher dose than the chart said to speed up the process, I'm currently at 70cc/day. How long does it typically take to see reduction in nitrate? I'm currently close to 30ppm.

Of note, I have 45 fish and feed heavily.

Just rethinking the amounts. 70 mL or 3500 mg acetic acid or roughly 1200 mg carbon. ~600 gal is ~ 2400 L. All this works out to be 0.5 ppm carbon. That does not seem like much carbon per day. Could be a while to see a significant reduction.

 

[tmz]

I deliberately kept kept my recommendation on the low side since the dosing is relatively new to the tank . 200 cc of vinegar gets you about .35 carbon dose per gallon.100 cc ( .175 seems low . but may be ok early on. It really depends on your tank and how it and it's inhabitants react. I dose about .5 per gallon,the equivalent of 348ml of vinegar as a mix of vodka and vinegar but have been doing it for about 10 years and have plenty of extra surface area for bacteria to colonize without becoming a nuisance.

 

[Nanook]

Well, I am dosing 160cc/day vinegar and nitrate is 26 still. Added 10cc of vodka to the mix to see if it helps lower that level. Phosphate is .06-.07. I've reduced feeding some to control that variable as I've added several nice acropora frags and have more coming in a couple of weeks. I'd really be okay with nitrate of 26, but the problem for me is that it will continue to rise.

Skimmer is pulling out much thicker, nastier, foamier stuff, so I think bacteria might be starting to increase a bit. Plenty of green algae on the glass every couple of days.

 

[Dan_P]

Skimmer is pulling out much thicker, nastier, foamier stuff, so I think bacteria might be starting to increase a bit. Plenty of green algae on the glass every couple of days.

A thicker foam can occur when the concentration of skimmable material decreases in the water. Also, running a skimmer to produce dry foam means it is removing less material per unit of time. Whether or not a better skimming rate will help reduce your nitrate level, adjusting your skimmer to produce a wetter foam will remove more material from the aquarium per unit time.

 

[tmz]

That amount of 80 proof vodka equals 80ml of vinegar.btw. The nitrate may not continue to rise as the increased heterotrophic bacteria take up the N from ammonia cutting off the nitrate production and should with time ,a month or two drop down a lot.

 

[Nanook]

Is it necessary to add a second dosing pump for vodka? Can I just add 10cc daily at one time?

 

[bertoni]

Dosing it in one shot should be fine.

 

[Nanook]

Dosing it in one shot should be fine.

Three for me one for the tank:clown:

 

[tmz]

You can dose the vodka at one time/bolus dose it. The ethanol does not cause a short term precipitous drop in pH like acetic acid in vinegar does which is one of the reasons I prefer vodka for the most part.

If you go with 3 for me one for tank; all of your tanks will probably look better to you.

 

[Nanook]

I’ll see what happens here I guess, do you think I should change my ratio of vinegar to vodka? I’m currently 160cc vinegar and 10cc vodka.

 

[tmz]

Generally, I don't think there is much difference beyond the ability to dose ethanol at one time vs acetic acid which drops pH precipitously in the short term when a large amount is dosed at one time but puts some back in it's journey to acetate . At the end of the processes both acetic acid and ethanol have a similar and equal small lowering effect on pH.

Ethanol( as in vodka) is CH3CH2OH; bacteria( acetobacther /AABs) oxidize it to acetic acid ( aka vinegar/ ethanioc acid CH3CH2OH); just like wine turns to vinegar. The acetic acid goes to acetate including the acetic acid formed by ethanol oxidation.

Some hypothesize that the ethanol oxidizing bateria (AABs) consume a bit more phosphate than when just acetic acid is used but I haven't seen any firm evidence of this. The acetobachter/AABs do ,however, fix nitrogen and may have some additional effect in NO3 reduction, particularly when bolus dosed.

FWIW , I settled on 36 ml of 80proof vodka( equivalent to the carbon from 288ml of 5% acetic acid vinegar) and 60 ml of 5% acetic acid vinegar as a daily maintenance dose for 700gallons and have been in that range for about a decade. PO4 is around .02 to .04 ppm with NO3 around .1ppm in the heavily fed system.