I am not a pro. From my experience, 20# of FHM will be 4000 to 6000 fish. My pond is about the same size as yours and I started with a lot less. With the water cooling quickly, I would not count on much spawning activity until the water warms to 55 F or so next spring. You should also count on losing some of the largest ones over the winter as FHM have a very short life span.

Just my thoughts...maybe one of the pros will throw their 2 cents into the discussion.

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