For what it's worth I was going to fertilize a pond this spring back when I was going to attempt to produce my own perch. (I was afraid with the VHS scare I wouldn't be able to buy any interstate). Anyway, my past perch producer was kind enough to tell me what to do. He told me to drain the pond for the winter and after filling fertilize immediately. Here's the important thing he told me: Fertilize right away before an filamentous algae forms. He said if you fertilize too late you will never get rid of the filamentous algae and you will just be feeding the filamentous algae. Sounds like that's what you're doing.


If pigs could fly bacon would be harder to come by and there would be a lot of damaged trees.