Filter's Digging a Hole in the Sand

In a 55 it shouldn't be that bad. Where is the spray bar located?

I'm using mine in the 75 gallon and it fits perfectly on the side wall.

I would cut the spray bar to fit on the side wall of the 55 and then drill the holes out a bit to disperse the forcefulness of the spray.

Or

Aim the spray bar more straight then down and the force will hit high and spread from there.

In the 75 I have it just under the water and pointed straight enough to where there is a ripple on the surface but the flow goes the length of the tank to the intake. I also have a PH on the right side in the back to push the water back to the left towards the Penguin 200 which sits in the middle of the tank.
 
Just to clarify, I love my xP3. I guess with the over filtration and the smallish load on the tank, it doesn't have to work very hard. I pulled everything out for a quick rinse and there was nothing to it. Only the polish media had some debris. Awesome.
 
Right now I have it aimed so that it hits the back glass, not pointed toward the middle of the tank. Should I reverse it?


I would reverse it. With all that force hitting the glass a mere half inch or so from the bar its forcing it downwards at a good clip. Facing forward gives it 12 inches to spread out and disperse.
 
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