You may not want to chance it but here is my experience. I applied rotenone in my small pond in spring. I'm sorry I didn't check water temps but I think it was in April and in about four days I checked the water with fatheads in a cage. They lived through the night so I stocked my pond with fatheads and a few days later catfish. The ootenone broke down fast and the hotter the faster (Texas can be pretty hot already in April).