Hi there. I using one 2L coke bottle on a 10 gallon tank. It produces more than enough
CO2 for me. It has been running for 3 weeks. I have two other tanks, a 25G and a 10G, all heavily planted. The growth and health in my plants in the tank with
CO2 is far better than in the tanks without. There really is a huge difference. One other thing, once you start your
CO2, you gotta keep it going. Injecting
CO2 is going to lower your
PH. If you stop and start it up again, your
PH will rise and fall all over the place. Mine ran out once and over night my
PH rose from 7 to 7.6. Not to good for your fish. If you don't already have one, go out and get a test kit. Keep an eye on your
KH and
PH levels. These levels can also be used to calculate how much
CO2 you are getting. It's really not alot of work and well worth doing. Good luck and keep us posted.