Worse comes to worse I will cut a spot for my powerheads. I looked again after BfishLpond's comment and counted...I have eight powerheads of various flow ratings laying around. Koralia's, Hagen's, other stuff. I definitely realized this before I did so, and there is a spot on each wall with just foam / no rock to be cut out in anticipation
I'm anticipating the need for at least three powerheads to eliminate dead spots, getting behind the structure in the very back will be the fun part once the rock structure is in place.
Ro/Di filling up:
