I've got this and it seems to collect on the leaves of my plants, but can be knocked off easily. Some of it settles on the bottom. I've got a bunch of it, and I'm not sure if it's algae or something else. If I had a better filter, I could probably get rid of most of it. I am trying Excel. Any thoughts anyone? Susan W _______________________________________________ GSAS-Member mailing list GSAS-Member@thekrib.com http://lists.thekrib.com/mailman/listinfo/gsas-member