Keeping Fish Outdoors in Cold Climates

[BBradbury]

Hello. I have a 300 gallon outdoor trough and keep Koi and Goldfish in it. No filtration, just aeration and of course a submerged water heater. I remove and replace roughly a third of the water twice a week and feed a variety about once a day. Koi can live up to 40 years in good water conditions and Goldfish possibly half that. But, the water must be kept extra clean, unless you have the money for a water filtering system. Even then, regular water changes are an absolute necessity. Before committing to such a project, you'll need a good working knowledge of proper tank preparation and general water care. This isn't like an indoor tank.

B