Vinegar dosing additives

[ReefsandGeeks]

I've been throwing an idea around in my head and wanted to get some input before just jumping in. I've been dosing vinegar for a long time to keep nitrates low and it ahs always worked great for me. I, however, have always had problems keeping pH in a normal range. I'd have been lucky to get it up to 7.8 normally, with it normally being closer to 7.4 or so. Recently I added some pH buffer until I was into the 8s, but as expected, my alk was too high. I've been trying to think of a way to continue carbon dosing, but without decreasing the pH of my system.

One idea I came up with was to dissolve some crushed coral or Ca reactor media in the vinegar prior to dosing the tank. This would raise the pH of the vinegar solution, and also double as a Ca and alk source for the tank (I think). I'm not sure if the alk and Ca would precipitate out of the vinegar solution or not, but surely the pH would rise. I'm also not sure if this would counteract the carbon dosing benefit of the vinegar as it dissolves the media.

In addition to adding the reactor media to the vinegar, I was also wondering if there could be any benefit to mixing coral food in vinegar just prior to broadcast feeding the tank. My thoughts are that the acidic vinegar would just start to digest the food a bit so the coral may have an easier time processing it. This one is a bit more abstract, but I have tried it twice now and may get slightly better PE after this vs mixing the coral food with just tank water. That could very well be the placebo effect though, and of course I've only tried it twice so far.

 

[bertoni]

Adding some crushed coral will act as an alkalinity and pH supplement to some degree, by dissolving the calcium carbonate, but I don't see any advantage to dosing in combination with the vinegar. It's easier and just as effective to dose a high-pH alkalinity supplement like sodium carbonate or something similar on its own. You could dose the two at the same time to minimize the pH effects.

Adding vinegar to the food might encourage more polyp extension by breaking the food down and dumping organics into the water column. It might make the food a bit easier to digest, but I think that the effect will be minimal.

I'm skeptical about the pH 7.4 reading. That's low enough that live rock might start dissolving. Most readings that low end up being some sort of measurement error.

 

[ReefsandGeeks]

Do you mean adding sodium bicarbonate directly to the vinegar prior to dosing, or simply dose the supplements at the same time, but separately? If you mean mixing them together before dosing, would there be any issues with mixing vinegar and kalk directly (not in top off water, but only vinegar and kalk powder) so it would be carbon dosing, alk supplement, and Ca supplement all in one?

I figured adding the food to vinegar would have a minimal effect ,if any. I'm not sure if I will continue or not. I may short term, then stop if I don't see some continued benefit vs simply adding the food normally.

I was always iffy on the reading as well, but it seemed consistant with several testing methods over a long period of time. I tried the drops in a test tube, strips, and pH pen calibrated with commercial pH fluid. It's possible there could be some error, but I'm pretty meticulous with my measurement techniques. It hasn't been as bad lately after raising my alk, and in the same time frame I've seen a lot more growth from my SPS. My gut feeling is the pH was too low for efficient coral growth, and raising my alk higher than normal was able to bring the pH into a more acceptable range. I can't back that up though, obviously my alk was raised at the same time so it could be more directly related to that, or something else entirely.

 

[bertoni]

I would dose the supplements at the same time, but separately. Combining them doesn't do much. You can mix some of them together, as well, without problems. The vinegar would act to dissolve some impurities in the Kalk, which might be a disadvantage, but otherwise, it'd be fine. Adding calcium chloride and baking soda or sodium carbonate would cause precipitation, and I'm not sure that the vinegar would be able to redissolve all the calcium carbonate.

If the 7.4 reading is correct, then I suspect that your house has a lot of carbon dioxide in the air. It's also possible that the dKH measurement is off.

 

[tmz]

I use kalk for almost all of my alk and calcium supplementation ;it uses CO2. I also use a CO2 scrubber to deplete CO2 form the air entering the skimmers. These two methods keep pH around 8.15 to 8.35 alongside daily separate carbon dosing.

 

[hkgar]

I am dosing a 50/50 vodka vinegar mix and running a CO2 scrubber in conjunction with my skimmer. Adding crushed coral is only going to increase your dKH as the buffers did. I also have a calcium reactor. My ph range is 7.7 to 8.0. A scrubber will increase the ph about .2

There is NO other way to increase PH.