I have a Coralife Biocube 29 reef tank. I am having an issue with water flow. Initial I had 2 of the Hydor Koralia Nano 420 power heads on a Hydor controller. I am getting a lot of brown stuff in the live sand. Also a little red slime on the live rock. LFS says it is a flow problem. Suggested I try adding a Hydor Koralia Evo 600 to tank and move one of the 420's to push water across the back of the tank. When I put my hand in front of either the 420 or 600 I only feel water flow within about 2 inches of the power head. Admit I am just getting back into reef aquariums after being away for about 10 years. I would think I should feel more water movement further out from the power heads. Am I right or wrong. Any info proided will be appreciated.


