We just moved to spray bars on each side of the tank, one powered by a Mag7 and the other by a 9.5. (the Mag7 needs to be replaced by another 9.5 it's weak). Holes blowing both across the surface to the front of the tank and some blowing down from bottom of the bars. All I can say is, Wow what a difference! Angel keeps things very tidy in there, but when I first fired it up, you could see the crud litterally rolling up into the water to be grabbed by the overflow. I got some pics I'll try to post this evening if time permits.
No more ugly powerheads to clutter up thing walls, and fall creating massive sandstorms and general havoc on the reef. Looks like great flow everywhere in the tank with varying areas of med to high areas. Haven't found any real dead spots yet.
I changed out the weir box to a monster that's using two 1" downpipes... talk about the ability to move some water! Both return pumps running full bore and the downpipes can handle it with plenty of room to spare.
Just need to whip together a new skimmer or something to feed the downpipe directly into to manange all the microbubbles being generated by the new downpipes. Might as well use all the air for something productive like skimming. The turnover rate is so fast the bubbles don't have enough time to rise out of the sump before being sucked up into a return pump and filling the display But without doing any real math I'm guess turnover through the sump is now is close to 1000gph or more.