I figure it is a transference thing. We humans like to keep the air cooler inside then the air outside. So we figure the fish would like a tank cooler then the ocean. :lmao:
It really depends on the inhabitants of your tank. But that is basically tropical ocean range. The more important thing is what is the full range? You say it is reaching 80 and 82, but not what it is reaching it from. 82 in itself isn't bad, but if your starting point is in the mid 70's then it could be.