How much flow is too much flow?

[mugginns]

How much flow is too much flow?

I just picked up two Aquaclear 802's (400gph) from Petsmart (27.99 online - pricematched down from 56.99!!!). Will this be too much flow for my 40B with live rock and corals (at some point)?

[roka64]

If my math is correct, that should be about 20x overturn. That is probably a good flow rate for your tank. Too much flow would be indicated if your fish can't swim around without being knocked all over the place.

[mugginns]

Ah, good idea. I am still in the setup stages, so I don't have any fish in. I bet I can turn down the output if need be though.

[melosu58]

I think you`ll be OK. Like Scott said you`ll be able to tell by how much your fish and corals are getting knocked around.