Newest additions to my fishtank collection (future polypterus tank)

[spit.fire]

any ideas of how much flow i should have for a return pump on my 25 gallon sump tank? The main tank is a 90 gallon

[mikebike]

I can not tell from the photo, do you have plywood on top of the 2X4 frame?

If not the 2X4 around the rim of it may get pushed down and allow the vertical support post to put too much pressure on the bottom of the tank.