air pumps

ive noticed that neither my pumps nor any others ive looked at list the volume of air they pump. how do i know im getting enough air if none of these damn things that info? anyone have a particular pump they would suggest using, i.e., make and model?

doesn't take much of a pump to be sufficient, it seems ... in fact, I have heard of the larger pumps needing to be turned down, because they were causing too much foaming of solution, and not circulating well ... :jointsmile: