MP40 and sand size

[Jfish]

I have a standard sized 75 gallon and keep my mp40 about six inches from the top. I have fine sand but the mp40 was added after about six months after the sand had matured a bit. No major sandstorms unless my clowns start digging in. I like it near the top as the rockwork doesn't get in the way when trying to create a wave and it seems to create a nice undertow moving across the sand towards the mp40.

I've also tried positioning it closer to the the bottom. Maybe six or seven inches from the sand but had to move in a couple flat pieces of live rock where it wanted to blow the sand around. Either way has great flow and fun to play with the differnt modes.