Two rules of fish kills:
1. There are more dead fish than what you find.
2. There are more fish left alive than you think.

I'd let things warm up and do sampling by all possible methods - observation, angling, feeding, seining - to see what you might actually have left alive. If you want to stock FHM, GSH, and RES without final results, none will be a problem if any of your previous species remain. If you plan on feeding, you can stock HSB anytime, but may want to let the FHM/GSH forage base establish first.

Smart Winter aeration (with a shallow diffuser) can prevent most Winter fish kills, and prevent their severity. (I think I channeled a Listerine commercial there.)

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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