So /an/, can I keep koi in my backyard pond? It's a large artificially-dug one, around 30-40 ft square and about 3-4' deep. I know people keep koi in those little plastic lined ponds, wouldn't they be way happier in something nice and big, with lots of bugs to eat? It's a little muddy and already has some wild descendants of feeder goldfish in there, and has plenty of cattails and waterlilies for shelter. I'm in upper new england so it freezes over in winter, but nowhere near all the way through.Whatcha think?
I see koi in natural ponds all the time here in Japan, but they all have a source of filtration or at least new water. If it's just a stagnant pond out there I doubt they'd last very long.
you're gunna need a fucking massive filtration unit, which will cost around 400-500 pounds, or probably any thing up to $1000, otherwise no problems, it might be a problem if its in direct sunlight mind.