I have a 40gal with an Emperor filter. I just added a skimmer. There's dirty water in the tank, the color of weak tea. I have 40lbs of LR. The tank is about a month old, with 6 snails, 5 hermit crabs, 2 shrimp, a blenny and a wrasse. Do I need both the filter and the skimmer? Am I accomplishing anything running both?