Looks like you've got some mermaids cup, turf algae and a couple types of caulerpa in there. My advice is that your fish probly won't eat it. If possible, take the rock out and scrub the living crap out of it. Use a couple of rinse buckets and make sure that the rocks are rinsed well before you put them back in the tank.
RO/DI water would be a definite help. What kind of skimmer are you running?
Christy
