What powerheads to use?

[littleprince]

On a 20 gallon.

I've heard a lot of horror stories about the rios.
And some about the Maxi Jets.

What about the aquaclears?

[gcvt]

I agree - don't waste your money on Rios. Aquaclears and Maxi-Jets are both fine powerheads. Two Maxi-Jet MP400's or a couple Aquaclear 101's might work well for you. I use Maxi-jets mostly.

[Elmo]

I've never used Maxi-jets, but I like my Aquaclear.

[littleprince]

I ended up with a minijet 400 and maxijet 400. These things look solidly built. The construction is much studier than my aquaclears. Cant wait to get the rest of the tank up and running.