is there a point when its just too much filtering on a tank and becomes redundant? I have a 75 gal that im growing out some stuff in and the stock is as follows....8 dats 3-5 inches, 6 inch poly palmus, 6 inch EBJD, 2 small silver dollars, 3 cory cats, 3 angelfish (dithers!)....I currently have 2 rena xp3s on it...water parameters are all good...I have an eheim ecco pro 2236 laying around should I add it or is it just overkill?..the 2 xp3s have eheim substrate, filter floss, and the foam pads..what do you guys think?