I have a Mag18 return at the top of the tank/a Tunze 6100 midway
in the tank and a Tunze wavebox midway opposite side of tank.
It took a few days of watching the sand and adjusting the inlets on
all pumps,but I did find a sweet spot that didn't move the sand.
I did have one spot I couldn't get it to stop blowing around and
I took a flat small rock and put it on top of the sand,problem solved.
Adjustment and patience is the key factor.
My giant Squassmosa does a number every week or so,
but that is what maintenance is all about.