Hi! I used the PVC piping in my 72 gallon bow front and put the pump in the middle of the reef and had it almost the length of the rock formation with holes drilled every half inch pointing up and it pushed the water up and through the LR.
In my 80 gallon reef tank I have 2 RIO 2100 pumps(one in each corner in the back) pointing toward the front and with extensions on the pump pointed so it makes the water quite turbulent on top and keeps a steady flow of water on the substrate so any food moves around and up and eventually out of the tank. Johnny
