Powerheads and flow

[Slimkasey]

Need some advice.
Here are the dimensions of my tank, 30"w x 18"d x 24"h, 55 gal, 1 1/2" sand bed. With a 25 gal sump/ref.

My question is about powerheads, I have a Koralia 4 powerhead, with access to another, is ts too much for this tank or should I get the other one fixed and get it in, 1 really pushes around the the BTA, but it also seems too much for the week old firefish, they come out for feed, when I turn off the PH, but when I put it on, they're gone again.

Thoughts/advice?

Thanks, Steve

 

[emmett0122]

what size are the power heads rule of thumb is 40 to 60 times the tank volume. but you want to make sure that you get a nice random flow in the tank with areas from low to high flow for coral placement