I have a 55G tank (est for about 1 year) with a Wisper 60. The fliter is on the right side of my tank (which is about 49 inches in length, 13 inches wide, and 20.5 inches deep). The bottom of the left side always has more debris than the right side. I was wondering if having two Wisper 60's (which are good for up to 60G) is a good thing in a 55G tank? I was thinking, the more filtration the better, but is there a limit to how much? Will i be damaging the tank environment with two filters? please help