I didn't want to mention caulerpa taxifolia "seaweed". I was given some by a hobbyist, because he has too many growin in his sump. my tnak is only a 40 gallon size, but with the built in sump that takes up about 1/3 of the tank itself. Lots of pond sponged, then bio balls, Rio 1700 as the pump. Found it in a trash can, and since the wife wanted salt water fish, I made it, it's been two weeks. Rock are collected from local hobbyist selling for $2.00 a lb. I think they are tongan, and fiji. They do have some "algae" growin in it, but that is not the "seaweed i was referring to. Also, a very small Xenia pop up from one of the rocks, it seems to be doing OK. The nitrite reading yesterday was at 5.0 ppm, with ammonia at zero. Hope it is about two more weeks or so. Had five damsels, only one is left, and also placed two pieces of raw shrimp. hope it works out great. I only two 24inch flourescent light, but I think they are the coral lights.