is there such a thing as too much aeration in the fish tank?

[lunasmile]

I have a small tank 40 gallon, but I have three air pumps, my clown loaches seem to love it but I am not sure if there is something bad about it. there is a lof of current in the the tank too, and I have noticed that my 6 tiger barbs are not at the top anymore like always, they are not towards the bottom ...

[Martin Thoene]

I think the question you are asking is "Is there such a thing as too much aeration in a tank?"

Really, aeration produces current and that rather than oxygen saturation can be a problem with some fish. It depends how much water movement you are getting as to wether it is affecting the Tiger Barbs.

I have 20 in with my Clowns in a 6 foot tank. It has two Rena XP3 cannister filters returning through spraybars, plus an Aquaclear 500 HOB. Also, 3 small powerheads pushing water down the tank length. Two of those suck back water from the opposite end of the tank via one of my River-Tank manifolds. So plenty of current. The Tiger Barbs are at all levels of the tank. In actual fact TB's are mid to lower level swimming fish rather than top swimmers. This goes for most Barbs.

There is a condition where you can get micro bubbles suspended in the water which can cause fish problems, but this tends to be during water changes if the local water supply is super-saturated with gas. As soon as it warms up in the tank, the gas bubbles off and can be a problem.

Normal aeration bubbles are not a problem though.

Martin.