rise in water temp causing a bloom in microscopic algae or plankton or something like that.

The more nutrients that are in the water, the more plant life you will have, either planktonic, vascular or algae.

If your pond is warm enough in the summer for the CC to grow, then it might be too warm for the Trout to survive the summer.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).