I don't think the level in the skimmer should be changing that much. Is something getting stuck in the intake? What brand is it?
You will probably slowly discover a few things on the rock. It really depends on the source. TBS rock is absolutely covered. The stuff at my LFS looks like, well, rock.
You will probably slowly discover a few things on the rock. It really depends on the source. TBS rock is absolutely covered. The stuff at my LFS looks like, well, rock.