Water flow

[fkshiu]

On my 135 mixed reef (72x24x20) I have one Tunze 6000 on a single controller (1850 gph) plus an Eheim 1260 return split three ways (one looped back into the sump (~400 gph back into the tank).

That's not all that much but I have less live rock than most others have in tanks of this size and the rock is arranged to allow for Gyre-type flow - think of a racetrack with the water circling around the track and the rocks in the middle infield. So I've been able to get away with less gph and powerheads.