What fish to breed in tropical pond to make $$$

[Lucas9919]

I live in Toronto, Canada and I have a 600 gallon pond. I put rocks about 1/2 inch diameter so the comet eggs hide in the spaces between the rocks and survive. Now, a year later I have over 50 5 inch comets swimming around.

 

[fishisme]

I wanted to put a pond in, if it was warmer i would of, but it can get to -35c in the winter.. I dont want to have a big koi/goldfish in a 55 gal for the winter.. I would need like a 300 gal tank but that wont happen

 

[lousybreed]

I plan on putting in gravel on the bottom and plants in the pond for young refuge. 50 5 inch fish in a 600 gallon pond is a lot! Do you thin them out?