Aeration

[jrd77]

In my 40 gallon, I have a penguin 330 with 2 biowheels. Is this enough aeration for the fish? How would I know? Is an airpump needed?

 

[yhbae]

Your Penguins should provide enough surface disturbance for gas exchanges. If you are overstocked, then you will see the fishes staying near the surface of the tank. As long as the fishes look comfortable staying at all levels of water, you don't need to worry about not providing enough O2.