Low CO2 leads to high pH and high pH can be a significant concern. Is low CO2 itself a concern for uptake by organisms? I do not think that has been shown to be true in a reef aquarium (which is very different than a freshwater aquarium in that regard).
I have been reading about Samala and how She's useing a yeast reactor to provide C02 for carbon.(sounds real intresting
Do you have a link? In some applications it might make sense, but in many applications/purposes it would not (IMO).
CO2 is not a useful way to provide a carbon source for bacterial growth in the sense of providing energy the way that adding ethanol(vodka) or other organic carbon sources can. It is really only photosynthetic organisms that have a need for CO2/bicarbonate/carbonate to get carbon.
Many reef aquaria already have excess carbon dioxide. If the pH is low for the level of alkalinity, then there is excess CO2. If a reef aquarium runs high in pH due to using limewater, typically) then it may be depleted in carbon dioxide. More aeration will help that, and reduce the pH,but in general, I do not think it is established that any of the organisms that we really want to keep need CO2 and cannot use bicarbonate equally well (and which is present at far higher concentration).
This graph shows the relationship between CO2, alkalinity, and pH:
which is from:
High pH: Causes and Cures
http://reefkeeping.com/issues/2005-03/rhf/index.htm
Just as a side note question. If you were dosing vodka,a carbon source @ 5-10 ml per 260gal,how quick does the reactions take place? As I understand it, carbon reacts to sea water and forms carbonic acid,bicarbonates,and carbonates.
Would the carbonic acid be strong enough to kill,or melt an Aiptasia spp.by injection?
Bacteria and other organisms take up organic carbon like ethanol/vodka, vinegar, and sugar. They consume it, get energy from it as you do from food, and release at least a portion of it as carbon dioxide. It can happen fairly fast (hours or less, likely).
Adding carbon dioxide avoids that process, and avoids the "benefit" of driving the bacterial growth.
Direct injection of soda water (CO2 dissolved in water) might be beneficial for killing aiptasia, but I've not seen anyone try it. It will be hard to do with the bubbling and all. Other supplements work well in that regard, such as a lime slurry.
=106:16:1?
