Assuming you are talking about a powerhead for circulation and not a sump pump, like a Mag, then it sort of depends on what you plan on keeping. The Rio won't be too much for LPS
's or softies as long as they aren't positioned directly in front of it. If you plan on having any SPS
's, one isn't enuff.
I personally recommend the new Hydor Koralias. You get a real nice WIDE flow as opposed to the strong narrow flow from a normal powerhead. I have 2 Koralia 3's (850 gph
) and a RIO 600 (200 gph
) for circulation in my SPS