I'm designing a planted discus freshwater 210. Since clean water is especially important with discus I'm thinking of running three canister filters with all intakes on one end of the tank and all outflows on the opposite end. I would like to put a solid rock base on the intake end to make vacuuming and changing pre-filters easier.
I think you're right, as long as I follow the proper flow rate as to not make the current difficult for the fish then a one way flow should be very effective towards a clean tank. The entire end of the tank on the outflow side will be a smooth rock bottom for ease of vacuuming. I'll also keep inflows high (near the surface) and outflow low (near the bottom) with pre-filters.
Not bare bottom, low tech plants...it just adds so much