Hi Guys i measured my tank and it is a 65 g. I brought two koralia powerheads flow rate 3200l/h and 850 gph is that good enough?
I had 2 Koralia 3s on a 55 standard (36x18x20), very similar to a 65. Worked very well
I have 2 #4's, 3 #2's, and a nano in my 55gal, it makes for a very chaotic but not overwhelming current. If you have enough water pushing off walls, overflows, rocks, and opposing currents it makes anything but a laminar flow pattern.
bill