I am in the process of cycling my tank. It is a 75 gallon tank. We added 35 pounds of live rock (10 pounds a week) so far along with 40 pounds of live sand and 40 pounds of sythetic sand. We then added two chromis and a freekin nemo. After around 16 days we had this brown film which I am assuming is the "wonderful bacteria" we have been waiting for. We then added 10 small hermits and 2 snails. After another week (week 4) we added 10 more baby hermits. It is still very brown on the surface of the sand and on the rocks and glass. Is this normal? :? I have also noticed some pretty aqua and pink colors spreading over my rock. I hope this is a good sign!