Sorry. I got my acid wrong. What I read fit the symptoms of my fish. Forgive me if I get it wrong, but I understand that a pond can turn over and release this (H2S), which damages gills and fish die in stages over a period of time. The SMB were the first and most extreme casualties, and the number dead closely equaled the number stocked. They were only 2 years old (12 inches),so I doubt any reproduction. Over the next five weeks, I continued to find around 20 per weekend dead--all species. I would see struggling fish in the shallows. The last dead fish were grass carp, a couple GS, and just a couple HBG. I have seen no sign of any fish since, and normally they are everywhere and have been easy to catch. I managed one ice fishing venture, where I probed the middle and deepest regions. Absolutely nothing.
The pond is a little under an acre, 12-14 feet at its deepest, square shaped, and does receive some wind. The north shore has trees, but the rest is covered in fescue. All banks are rather steep except for the four corners. I have little aquatic vegetation other than some WP.
I plan on having bottom aeration put in this summer, assuming I'm not wiped out by some medical bills I've encountered recently. I've contacted several sources in 3 different counties (health depts, local dnr, farm services, etc.) and can't find anyone to do a water test. I've even made a couple calls to Indiana. I hope I'm wrong and am just being impatient, but the changes in the pond and its inhabitants are definitely disturbing. Anyway, I must decide fairly soon if restocking will be necessary--if even possible. Again, I thank all.
