How do you dose organic carbon? Poll!!

[Reefbuds]

If you dose organic carbon in your reef, how do you do so. Vodka, vinager, sugar or NOPOX/DIY, other or not at all? If other please explain.

 

[Orm Embar]

I add vinegar to kalkwasser for more potent kalk; I figure a small amount of carbon dosing is fine. I don't specifically dose carbon for nutrient reduction, however.

 

[Reefbuds]

^

 

[beaslbob]

other I don't LOL

 

[redfishbluefish]

I'm an "other." I dose a DIY version for NOPOX that is made by mixing 375 mls vodka (80 proof), 500 mls vinegar (5%), and 125 mls RO/DI.

 

[andrewkw]

Same. DIY Nopox.

 

[Reefbuds]

What are the advantages of nopox vs straight vodka?

 

[AdamNC]

Red Sea NoPoX

 

[Potatohead]

Nopox via GHL doser.

What are the advantages of nopox vs straight vodka?

Based on what Red Sea says, it does a better job of maintaining different bacterial cultures rather than one large one. This allows complete denitrification whereas with an 'unbalanced' denitrification you can end up with ammonia, nitrate, hydrogen sulfide as a result because the process is not 100% complete.

There is a reefbuilders video on YouTube with Sharon from Red Sea who explains it all. He is their head chemist. It could be a lot of marketing mumbo, but since it is coming from the guy who designed it, it holds more weight IMO.

 

[Randy Holmes-Farley]

Based on what Red Sea says, it does a better job of maintaining different bacterial cultures rather than one large one. This allows complete denitrification whereas with an 'unbalanced' denitrification you can end up with ammonia, nitrate, hydrogen sulfide as a result because the process is not 100% complete.
.

They may say that, but there are no such advantages that have ever been demonstrated. I'd be surprised if it is any thing more than speculation on their part, but there's certainly no data that's been released to show any differences from, say, pure vinegar. :)

The unbalanced part is just utter nonsense. There's no scientific rationale how using vinegar could produce hydrogen sulfide when a mix of organics would not. Just total crap, IMO. :(

 

[happyhourhero]

DIY NoPox

 

[Randy Holmes-Farley]

IMO, the biggest differences between the the organics used are the propensity to create a cyanobacteria problem (which may depend entirely on the species of cyano present in each tank, so may vary tank to tank) and the number of organisms beyond bacteria which take up each organic.

Contrary to popular belief, many of them are readily taken up by corals, and a multitude of other large organisms, and even some types of algae.

 

[Reefbuds]

Interesting. Why do you choose vinager over vodka or sugar Randy?

 

[Hans-Werner]

I don´t think that all organic substances work the same way. It may be quite similar with vodka, sugar and acetate/vinegar. I have seen that in the same system the buildup of bacterial slime is higher with the addition of sugar than with another substance I have tried. I also tried calcium acetate (what you get if you mix calcium hydroxide with vinegar) which is very quickly metabolized in the whole tank so I stopped dosing it. I am not sure why the corals did react different but when bacterial slimes formed the corals reacted in a negative way. I have seen that in several polymeric substances the corals reacted in a very positive way after just some days and started accelerated growth.

I have following theory: The coral today is called a holobiont which means it is a consortium of mutualistic organisms consisting at least of the coral animal, the zooxanthelle and diverse bacteria on and inside the animal. The zooxanthellae fix inorganic carbon and since they are nutrient limited in their growth they release it to the coral animal as organic carbon of various kinds. If the coral animal is also nutrient limited in its growth it releases the organic carbon as slime and other substances to its surface and into the surrounding water. But the inner and outer surfaces of the coral are covered with mutualistic bacteria. These bacteria grow on the organic substances the zooxanthellae and the coral animal releases and produce vitamins like vitamin B12, and they are more efficient than the coral animal in taking up phosphate from the surrounding water. The coral animal feeds on these bacteria it grows on its surface and takes up vitamin B12 and phosphate in this way. These mutualistic bacteria are adjusted to the subtances the coral releases. If you dose these or similar substances to the reef tank the coral holobiont benefits more from the organic carbon dosing than if you dose other substances that mainly nourish opportunistic bacteria that live on the glasses, sand and rocks.

It is just a theory I can´t verify but I am sure that there are differences if you try more than just one or two common substances.

 

[Randy Holmes-Farley]

Interesting. Why do you choose vinager over vodka or sugar Randy?

Two main reasons, but before I give them, I want to be clear that I'm not claiming it is best. People have good success with vodka and mixtures of vodka and vinegar, NOPOX, etc.

I do agree with Hans-Werner that I'm not a particular fan of sugar. I've heard of more negative effects from it, and the two times I very briefly and unscientifically experimented with it, it browned corals and anemones.

I started with vodka when I took up organic carbon dosing, but cyano became a problem in my tank, so I switched to vinegar. After the switch the cyano went back to its previous levels in my tank, which didn't concern me, so I stuck with vinegar for years after that.

Acetate from vinegar is perhaps the most common single organic chemical in the ocean, especially in terms of the amount metabolized each day. I've seen studies where the turnover/metabolism of acetate provides the largest fraction of metabolism of organic matter in sediment pore water. It is also very widely taken up and used by organisms. Corals, sponges, etc. Is there a reason to only want to drive bacterial growth? Why not directly help support the growth of many of the larger organisms in the tank?

 

[Reefbuds]

Hmm interesting stuff. It seems vodka isn't very popular these days. That's what I use

 

[Reefbuds]

^

 

[Flameback Pair]

Are those of you who dose vinegar with or without kalk putting it in your ATO reservoir? Because if you are I would like to know if this causes a lot of bacteria to build up in there and slime it up?

 

[Randy Holmes-Farley]

Are those of you who dose vinegar with or without kalk putting it in your ATO reservoir? Because if you are I would like to know if this causes a lot of bacteria to build up in there and slime it up?

Bacteria cannot grow when the pH is very high, such as in saturated limewater. So there's no concern about bacterial growth as long as you add enough calcium hydroxide. :)

That said, I prefer to dose vinegar from a dosing pump to get better control over when and how much vinegar is dosed. For example, I would not want to dose it in the late evening or night when the pH and O2 are lowest since it tends to lower both.

 

[Randy Holmes-Farley]

Hmm interesting stuff. It seems vodka isn't very popular these days. That's what I use

I still see lots of folks using it. :)