What's your opinions, guys? Discuss! This is a topic that interests me
I've noticed lately the trend in CO2
injection for reef aquariums. I've seen it for a while in planted tanks, but exactly how useful is such injection in a reef tank? It is my understanding, through some research, that CO2
lowers PH of the water and can cause corals and the calcerous skeletons of corals to disintegrate due to increased water acidity. Here are a few small snippets from some sites on CO2
1. Influence of carbon dioxide on alkalinity
Carbon dioxide can change the pH of water. This is how it works:
Carbon dioxide dissolves slightly in water to form a weak acid called carbonic acid, H2CO3, according to the following reaction:
+ H2O --> H2CO3
After that, carbonic acid reacts slightly and reversibly in water to form a hydronium cation, H3O+, and the bicarbonate ion, HCO3-, according to the following reaction:
H2CO3 + H2O --> HCO3- + H3O+
This chemical behaviour explains why water, which normally has a neutral pH of 7 has an acidic pH of approximately 5.5 when it has been exposed to air (http://www.lenntech.com/hazardous-su...on-dioxide.htm)
2. "As atmospheric carbon dioxide levels continue to rise, so do the levels of dissolved carbon dioxide in sea water. This leads to an increase in ocean-borne carbonic acid, which is capable of dissolving calcium carbonate. 'This is a major problem for corals,' says Maoz Fine, a marine zoologist at Bar-Ilan University in Israel. 'Essentially, acidification leads to naked coral.' " (http://www.bioedonline.org/news/news.cfm?art=3235)
We know that the zooxanthellae within the corals photosynthesize to provide nutrients to the coral, therefore CO2
is of use to the reef aquarium, but...and here is where we discuss...
1. What would one have to do to keep the PH stable in such a tank that is being constantly injected with microbubbles of CO2
? Would it be worth it? The cost of a calcium reactor (to maintain alkalinity and resistance to PH change) + a CO2
reactor is probably fairly expensive. (God forbid the bubblecounter breaks or your kid turns up the CO2
pressure, I've seen entire tanks of fish die that way).
2. That being said, would it even be worth it to have a CO2
injection system? Why not just a calcium reactor+adequate lighting+adequate surface irritation to maintain gas exchange?
Alright, I want to hear everyone's opinions who have an opinion on this matter. I will be imputting my opinion sporadically, as I already have put in a few of my own 2 cents, but I am mainly playing devil's advocate. Hope this turns out fun!