Doug yes I do have a skimmer. It is an emperor aquatics skimmer rated for 150 gallons and removes lots of brown goey stuff( it is a bit small but I do have a deep sand bed). The fake rock are from a rather tried and true recipe. They are made from aragonite, cushed oyster shells and concrete (1 part concrete, 1 part aragonite and 3-4 parts oyster shells).
The trick is to cure them. I cured them for 5 weeks in fresh water (with frequent water changes and ph reducer) until the Ph remained constant. I then put them in the tank and they had another 5 weeks before anything was added.
Mostly it was just the first shipment of fish. I have 1 left and it is doing very well. It has stopped breathing so fat and is now firmly in charge of 1 side of the tank. My wrasse and clown fish are now doing very well and their overall condition has improved (especially the clowns).
The inverts are having problems. Each of them have started a molt and seem to have problems shedding their skin. In this state they seem to be prone to attack and ... well ... I am curently trying to figure out what could cause that. It has happend to all of them.
Thanks for the tips...and for sure no lecture came out of your post
