I live in Idaho and there is a hot spring here with several types of tropical fish here. People over the years have let many fish go in the spring. The water stays warm year round and feeds a small stream. The stream drains into the Snake River which is too cold for any tropical fish to survive. I have seen fancy guppies, several colors of mollies, several types of cichlids, tilapia, swordtails, goldfish, as well as others that i couldn't identify. I'mgoing back there this summer and plan to take pics. I have several friends who get most of their fish for the aquariums there, is this a good idea?