1 reason i changed to retrofit is becos i can on 2 tubes at a time instead. as for the reflector, i guess it does help abit too. the hopar did it job for my tank, juz that i juz wanted to try something else.
the K4 is much better of cos, but due to the increase in flow, K3 3200L/hr vs 4600L/hr, i have to remove my seio too. which is kind of gd news for mi, 1 less powerhead in the main tank........