Anyways, a single Fx5 would do the job if you dont overstock with other fish. We are looking at 1 ray here, it does not produce waste as a horse.. K1 sump would be the best choice no matter how you turn it around, BUT, and Fx5 would do the job just as good on this tank. You will not ever get Nitrate, nitrite and ammonia _below_ zero. Some filter systems on here should be able to tho 