plumbing for BB

[jsc0787]

I am going to empty my tank and go bare bottom. Was wondering if anyone had advise as to designing the flow for the bottom to remove detritus? The tank is a 1/2 cylinder 60x30. Was thinking of having my closed loop intake from there 1 1/2 inch intake split to 2 1 inch bulkhead at both corners. And having my sump return output split to blow the detritus around. any sugestions?