NO3:PO4-x conversion to vinegar

llandegfedd

New member
Hi, wondering if anyone can help me with a query.

I wish to convert from dosing nopox to vinegar, as I feel my knowledge of carbon dosing is sufficient to experiment with alternative forms of carbon dosing.

I wish to dose carbon via the acetic acid of vinegar, however am unsure of what the equivalent dosage would be. I.e. The dose to start at whence the remaining nopox has been utilised.


At present I am dosing 18ml of nopox in to just over 150USG what is the equivalent dosage of 9% distilled vinegar?

Thanks in advance,
Ben
 
I'm not sure we know what amount of what is in that product, so it would be pure guessing to try to match it.

What product are you going to use that is 9% acetic acid?
 
Apologies. I have just remembered that vinegar dosing is often utilised at 5%.

However my source will be ethanoic acid of 99% purity. So I can work to any concentration via the appropriate dilution.

Do you have a suggestion to a rough equivalence dose at 5% if you're familiar with dosing at that concentration?

Also could you see any reason to not dose a more concentrated solution than 5%, as minimising the top-up of the dosing unit's supply would be desirable.

Thanks, Ben.
 
The tubing that is normally used in peristaltic pumps might not be optimal in glacial acetic acid, so diluting it gives easier control in terms of mL dosed, and it might be easier on rubber parts if you use a pump.

I can tell you what dose I use for vinegar, but I have no idea what dose is equivalent to the NO3:PO4-x that you currently use..
 
I don't think you can equate the NO3:PO3 x with vodka and vinegar since the ingredients are proprietary. It smells like alcohol (ethanol? methanol?) an vinegar;may have some sugar ,all guesswork. I know my friends have good luck with the NO3;PO4x product as well as vodka and/or vinegar.
 
Okay. Perhaps you could suggest a dose if I tell you a little bit about my system?

It's just under 800L pre displacement, with just over 600L/160USG of water.

No dead spots in the tank, open aquascape.

A sand bed in the display varying from 1-3", which a large prevelance of gas pockets, which I can only assume are a product of denitrification.

There is a DSB in the sump, about 22"x8" surface area, with a 6" depth of sugar sized/oolite sand.
this DSB has only recently started to show signs of maturing, due to a few recent alterations.

We have an Avast mutiny O3 reactor to which we inject 125mg/hr, controlled by an ORP controller.

Skimmer is a bubble magus C7, skimming wet., I guess producing about 500-1000ml a day on average.

We have a refugium in the sump, however growth isn't anything special. I look at this area as more of a region for faunal reproduction than nutrient control.

We have a few reactors, one of which runs Biophos 80, an iron hydroxide based PO4^3- remover.

I guess they are the only relevant localities in the system where 'nutrient' will be affected one way or another.


Fish stocking load is rather heavy.

S. vulpinus, foxface.
A. japonicus, powder brown.
Z. flavescens, yellow tang.
C. tominiensis, tomini tang.
E. midas, Midas blenny.
5 Allen's damsels
7 Pseudanthias dispar, 1 Pseudanthias carberryi.
Centropyge bispinosa, coral beauty.

Feeding:
Mix of frozen, 4 cubes, a pinch or two of different flake foods, 3"x3" piece of nori, or a new era marine grazer.
We also have a culturing cabinet, that produces T. sueccia 200ml/day. Artemia nauplii ( a lot, added in the mornings for.the planktivores to eat)
Rotifers a couple times a week.
Reef energy A&B 10ml/day.

I'm also attempting a culture of calanoid copepod, though these are yet to take off.



Parameters related to measurable nutrient:

NO3^2- : 3.5-4mg/L
PO4^3- : 0.06mg/L. I tend not to go lower on phosphate, with a nitrate value of 3.5-4mg/L, as it appears to trigger an onset of cyano, I assume due to imbalance.



I am weary of starting as per the dosing charts, one can find online, as I am conscious of dosing too little and experiencing a rise in nutrient, or dosing too much, and strip the tank too quickly, or overdosing.

Any advice on the basis of this information would be much appreciated.
 
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I say to start at about 20 mL per day of 5% acetic acid, and ramp up as needed over a few weeks. You might dose over 100 mL per day eventually. :)
 
Thank you very much for that information Randy.

Out of interest, roughly how much is your maintenance dose on your 120G?

How would you personally recognise when addding more vinegar is surplus/excess to what is on the border of being dangerous/unacceptable?

Ben
 
Just reading that thread now Randy ;) .

So you're system pre displacement is approx. 330G, and mine is just over 200G. So in my water volume your dosage would be c. 60ml. But you have experimented with what would be my equivalent of ~250ml, at which point you witnessed that concentration being somewhat malificent.

Whilst I realise individual systems are highly variable, it does help to know a rough range I would expect to utilise, and an approximate far upper limit.

At a very crude estimate, £12/$20 versus £200/$340 per annum. There is quite an inventive to switch.

Thanks for your help R.

I will no doubt have a few more questions to ask you guys and girls on here regarding this change in the near future. :)
 
In reading through the threads it seems most folks settle in after amping up at about .4 to .8 ml of 5% vinegar per gallon of water volume. Personally, I use the equivalent of roughly 370ml of 5% vinegar for 650 gallons, about .6 ml per gallon and have used about the same dialy amount for 5.5 years to maintain low PO4 and NO3 in a heavily fed system.
When I use much more than that bacterial mats and/or strands appear in places I don't wan't them . Overdosing may also cause cloudy water and oxygen depleting bacterial blooms in some cases. Each tank is different in terms of nutrient inputs ,surface area for bacteria to colonize and other variables. I agree 20ml is a safe starting point particularly since your tank has been receiving organic carbon already at some unknown level from the NO3: PO4x which is probably not less than 20ml of vinegar will provide.
 
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Cool. Thanks always nice to get a second opinion.

Just to check though, this is pre-displacement gallonage, correct? Not a dose per gallon of water, but a dose per gallon of the total capacity of the system.
 
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The 650 gallons is the estimated total water volume of the system which includes the tanks , refugia and crytic areas areas full of extra submersed live rock and substrate ( capacity minus sand live rock ,partially unfilled vessels,) .
 
Well managed to get 2.5L of 99% Ethanoic acid dispatched today. Should arrive tomorrow.

I will dilute to 10% and dose an initial 10ml.

Since theoretically 10% CH3COOH will have a pH 2.26, would you suggest counteracting the pH reduction with a strong base, such as Ca(OH)2? If so, how much do you dissolve?

I plan to store the solution in a 5L container, and have read that neutralising the acid may promote bacteria to populate the container..

So should I halt the addition of Calcium hydroxide to the ethanoic acid until such time when I am dosing sufficient amounts so that the contents of the container is topped up every week. OR... should I not worry about bacterial congregation in the container? Or, is there no real benefit of trying to counteract the pH reduction by adding Ca(OH)2 to the dosing liquid...?
 
You can dissolve calcium hydroxide directly into the diluted ethanoic acid to saturation (I dose that way for a couple of years), or if you dose the diluted ethanoic acid slowly with a dosing pump over the course of the day, it won't cause much issue (I do that now).
 
Okay that's okay then, I'll just see how it goes for now, since the solution will be dosed over the course of the day.

Though I'm not sure whether to split the dosage over 24 hours or the daylight hours?


Another question, the solution will only come in to contact with tygon tubing, have you an idea of how concentrated the solution can be before it affects the tygon?
 
I split vinegar dosing over the light cycle only. :)

Hard to say on the tygon without knowing what is in it. It has the possibility to draw plasticizers out of the tubing and deliver them to the tank.
 
I'd dose the ethanoic acid over the course of the daytime hours when photosynthesis will offset the pH drop.

In my case, I dose 80ml of 5% vinegar all at once shortly after lights on in the 650 gallon system. With this relatively small amount of acetic(ethanoic) acid there isn't much pH effect.
I also dose ethanol( 80 proof/40% vodka); 30ml is bolus dosed in the morning with the vinegar and another 6ml at night.( The total vodka ,36ml ,is equivalent to 288ml of 5% vinegar in terms of carbon content.) The ethanol does not have the same short term precipitous effect on Ph;so, vodka can be bolus dosed.
Not sure that split dose of vodka at night is of benefit or not. Anecdotally, when I skip it, PO4 measures a bit higher in the a.m. , so; I'm guessing bacterial activity continues at night and since many bacteria split in 12 hours or so a continuous organic carbon supplement is useful to them.
 
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Is it totally necessary to dilute the vinegar ?? I'm dosing from a dosing pump straight vinegar throughout the day ? I never thought of diluting ... And now I'm concerned about adding plastic to tank water
 
No, It shouldn't be diluted lower than 5% acetic(ethanoic) acid which is standard white vinegar.
 
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