If it is a heavy plankton bloom, why would it be like that all the time? Also, I don't think there are any carp or catfish in there. I would hear them splash when I walk around the pond and there has been no sign of fish other than I saw a tiny little minnow the other day near the surface and I know the bass are in there because I dumped them in in April or May and the frog population is down. The only thing stirring up the pond is my two dogs, Lab and Rott who are in the pond every day. Lab swims with me while I'm in the paddle boat and Rot wades on the edge. I have had a jar of water sitting since Thurs night and it still looks the same except for some algae looking stuff that settled to the bottom of the jar, it's not green though, it looks reddish. I think I'll just take some pictures and put them on here so you can see for yourself.