I live in East Texas and it gets pretty hot here so, Atlantic Green Herring like I got in the Netherlands are not something I can get locally, at least fresh or alive. As I think about cold-water fish, I also think about Trout.

So assuming I built a small building with ~300-gallon tanks, is raising Herring or Trout practical? What would I be looking at to cool the water in Summer? I assume as long as it doesn't freeze solid in Winter it won't be a problem with brief periods of freezing weather with limited thermal warming from lights, pumps, etc.

Is raising cold-water fish like this impractical due to cost or complexity?

TIA,
Sid

p.s. I realize this might not be the best forum for this type of question so, a pointer to a more focused forum for a cold water closed ecosystems would be appreciated!