aquaclear powerhead

It really depends on your overall setup and arrangement, as well as stocking.
Do you have either a canister or hob filter on one end of the tank to collect the debris?
What kind of fish are you keeping in the tank, and how much cover is available for them to get out of the current?
I have an aquaclear 110 powerhead lying around that pumps a max of 900+ gph. My largest tanks are 75's, so I don't use it much or often. However, when I stir up a mess of pleco poop (3 L-204 Panaques) siphoning the tank that powerhead and a quickfilter attachment will make the water crystal clear again rather quickly.
One of my 75's has an aquaclear 110 hob filter on the left end of the tank, an aquaclear 70 powerhead and quickfilter on the same end to help circulate water, and an aquaclear 30 (also w/quickfilter) along with a Koralia nano on the right side to complete the flow pattern. Between the hob and the quickfilters there is very little debris on the sand in spite of all the rocks and driftwood in the tank.
 
It's a rubbermaid 300 gallon stock tank, will have 3 giant rapheals-28"; 1 albino channel cat-30"; Leiarius pictus-30", all will be bought as juveniles.

Decor will be nursery pots turned to caves and driftwood, floating plants.

Filtration is going to be 30 gallon tote(diy wet/dry) with 58lbs of seachem pond matrix, 200 pot scrubbies, and mechanical filter pads.

The pumps that will supply the water to the filter will be in the center, of the somewhat circular 300 stock tank.
 
If the tank is roughly circular with the filter intake in the middle your best bet would be to arrange the pots/driftwood to facilitate a circular current flow. I'd go with a couple of 70's, one at each end, to keep the water moving and shift debris toward the sump intake. A few properly placed rocks would help channel the debris as well. I doubt the 70's would make the flow too strong for the large fish, but if it's a bit much for the juvies until they grow out you can simply adjust/reduce the flow rate in the meantime.
 
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