Hi everyone, very new to this aquarium, it was an established tank I picked up. the skimmer is bubbling and skimming ok, but is also blowing bubbles out of the bottom. I thought this was normal, until a friend said it isn't. Ive had it apart and cleaned it in the past, but it did it before and after. Since its all underwater, I can't see where its coming from. Has this happened to anyone? Any ideas? Its a Simplicity 240. thank you.


