Those Danners are good. They are kinda large though. You can get them at Home Depot and other places under different names.
I use one of these 500GPH HydroThrusters:
http://www.aquaticeco.com/aquatic1v1...nfo4=0&eflag=0 in my testing setup.
I also have a Little Giant 170GPH Inline pond pump, a 200GPH submersible pump, and a 12VDC 500gph beilge pump for boats.