isnt that from the little bit that leaches from new pvc? its so small that most skimmers miss it.
Are you saying that PVC leaches some sort of molecule that gets skimmed? I guess I've never heard about that. At any rate, the system has had water running thru it for quite some time now, so I would think the inside of the plumbing is pretty well coated with whatever biofilm is going to grow there.
