C02 vs Fish

[CadillacSlim]

Hi,

Plant Noob here.

I was just wondering how you go about ensuring there is a good distribution of C02 vs. Oxygen for the fish? For example, I read that the main culprit for the dissipation of C02 is disturbing the surface of the water. The air stones obviously create a lot of disturbance and I am wondering about finding a happy medium.

I thought about turning off the air stones during the day and then at night when I kill the lights, I'd turn the air stones back on. From what I understand the plants basically stop eating when the lights are off and that it would make more sense to pump oxygen at night to keep the C02 levels from getting too high?

http://www.aquariumadvice.com/forums/f70/20-gallon-cichlid-tank-141246-3.html

Above link is my current tank. The C02 canister setup I purchased was one of the small fermentation ones designed for 20 gallon tanks.

 

[fort384]

It sounds like you have a pretty good understanding of CO2...

You do not want to run air during the day, as it will off gas the CO2 that you want to stay in the water for uptake by your plants. It is a great idea to have the air stone running at night after the lights go off.

While the lights are on, your plants are using photosynthesis, which requires CO2 and produces Oxygen. The more CO2 available, the more photosynthesis that takes pace, the faster your plants will grow (assuming one of the other nutrients required for the process isn't limiting it). At night, once the lights go out, photosynthesis ceases. Plants then go through what is called respiration. Respiration uses O2 and produces CO2. By also injecting CO2 at night, it can cause the CO2 levels in the water to raise pretty substantially. Running the air will offset all of this. I did it exactly as you described when I used DIY CO2... as soon as the lights went out, my bubble wall went on.

 

[CadillacSlim]

It sounds like you have a pretty good understanding of CO2...

You do not want to run air during the day, as it will off gas the CO2 that you want to stay in the water for uptake by your plants. It is a great idea to have the air stone running at night after the lights go off.

While the lights are on, your plants are using photosynthesis, which requires CO2 and produces Oxygen. The more CO2 available, the more photosynthesis that takes pace, the faster your plants will grow (assuming one of the other nutrients required for the process isn't limiting it). At night, once the lights go out, photosynthesis ceases. Plants then go through what is called respiration. Respiration uses O2 and produces CO2. By also injecting CO2 at night, it can cause the CO2 levels in the water to raise pretty substantially. Running the air will offset all of this. I did it exactly as you described when I used DIY CO2... as soon as the lights went out, my bubble wall went on.

Fantastic! I guess spending hours reading articles on taking care of aquatic plants has definitely been worthwhile. Thanks for the clarification and it has given me an even better understanding of the process.