I have a 60x48x20 main tank with sand. I want to replace my 4x 1200lph powerheads. The rockwork is mostly in the middle and at the back / The weir is at the back in the center. I don't want to see large powerheads at the front or at the sides as the water depth is only 20" high, and the tank is viewable from 3 sides; so that leaves just the back. My closed loop pipework returns the sump water through the center of the rockwork.
Would I be ok with 2x wp40's ? or maybe 2x wp60's ??. I want a lot of flow, but I need the sand to stay at the bottom, and the water to stay in the tank.