Seems like there could be more going on than just stratification. Is it possible what mixing you had initially wasn't adequate enough? Additionally do you possibly have a heavy fish load in your pond? Feed a lot? Pond an old one and very euthrophic?

Sorry for your loss.

Last edited by Cecil Baird1; 06/24/13 12:35 PM.
If pigs could fly bacon would be harder to come by and there would be a lot of damaged trees.