@marty9876 - I'm using a laminar gyre on my 300 DD (3 WP40 and 1 WP60); I'd recommend trying placing your WP60s two to an end, about 2/3rds of the way up from the bottom, at the 1/3 and 2/3 points. Try running them in alternating opposing patterns for about an hour each side, full constant speed. I'm using a Hydor wavemaker to control these.
This approach gets the entire aquarium volume moving in a gyre, lifting detritus up from the bottom and bringing it up to the top for removal. This also moves a substantial amount of water through the rock structure (I have a median reef, not a back wall, but this should work in pretty much any formation). Take a peek at the most recent issue of Coral magazine - they have a pretty good write up on flow and the reef aquarium, and provide much more detail than I have here.
These are turning out to be great, powerful, and quiet water movers.