Common themes I've seen on questions for items like this are:

1. Any recent fertilizer or weed killing treatments before the rain?

2. Pond Size and Avg Depth? Might also be helpful to know if the pond was full / close to full before the rain or was all of the water captured retained.

3. Have any water quality testing before/after the fish kill on PH and Alkalinity?

4. Anything visibly different other than the stained water noted between the rain event and fish kill?

I would be guessing but if you are currently aerating a pond turn over on water temps probably it's part of the cause. This assumes that you are aerating most of the pond and it's adequately sized/functioning properly.

Sad news on the loss of the fish. Hang in there.

1.5acre LMB, YP, BG, RES, GSH, Seasonal Tilapia
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