My tank is 3 1/2 months old. Is it to late to add a couple of live rocks? Will it change the water quality? I have a 55 gal. tank with the following: 404 fluval, biowheel, protein skimmer, air stone, uv, 1 powerhead, crushed coral, 1 marine beta, 1 fire fish (had 2 one jumped out of the tank...