My nano is coming along, but I can't get the nitrates down. Everything else seems fine. Long story short its my daughters tank so its fed everyday. The only things in there is 1 damsel, 1 emerald crab, 1 halloween crab, and 3 snails. Corals is just paly's and zoa but they aren't looking so hot. I do a 50% water change once a week. Whats on there now is a Aquaclear 70 HOB filter with a sponge and rubble rock and a small powerhead on the otherside. Should I just cut the feeding back to twice a week?