When is it necessary to put an Air Stone in your aquarium? As I've said I have a 10g aquarium w/ 3 rosy reds atm....I've read alot of ppl have air stones etc. I have a internal corner filter....the water pours from approx 1/2 to 1 in above the water level of the tank. Do I need an air stone?? I know very little about them overall. Thanks