It is easy to get chemical names incorrect. I suspect your fish kill was do to a strong turnover where water with no DO and loaded with H2S mixed up into the thin upper 5-6ft layer and ultimately killed most if not all the fish. As the summer progresses the H2S increases more & more to very high concentrations by late summer. Note there can be a few survivors that are small size who best tolerate DO loss. SMB are very sensitive to low DO and H2S so it makes sense they died first. I am positive the water coming out of winter is now good enough for restocking the pond. H2S relatively quickly dissipates and DO recovers to high saturated conditions by winter and then again in spring. If you install aeration and start it after May 20, begin aerating slowly for 1hr 1st day, 2hr second day and 3-4 hrs the 3rd day. Then the system can operate 24/7 if desired.
Last edited by Bill Cody; 03/08/16 08:14 PM.
