I have a 90 bowfront 48" long, 24"high with the overflow in the back center, the rockwork in the middle and it's BB. I want to keep detris suspended off the bottom. I just got 2 6000s and was looking for advice on placement and controller settings. I noticed that if I have them on each corner pointed to the front center and use pulse or interval 2 it forms a current in front of the overflow that blocks the surface skim from draining, also how high up in the tank should the streams be. Thanks for any advice.