For total movement, two of these do more than 15,000 GPH did with pumps, on my system.
Rating 8/10
-2 demerits for their bulk.
I just would like to know how the formula works for determining actual gph on these things.
If they are 17000 gph each, that would mean i have a total of 49,000 gph in the tank. :O
Running them opposite of one another works, but only if 2 side by side is not an option.
A more powerful wave is made by placing side by side...and the closer together the boxes, the better they work.
I absolutley love these things, if detritus/crap even has a chance of falling and sitting, it rolls back and forth until it is gone.
They are producing a 1.5" wave in there now, and i bet i could tweak em and get a bit more.
Thumbs up for these units.