I put fish in our swimming pool one winter when my dad decided he wasn't going to waste chlorine in winter.
First came the carp between 1-3kg, they spawned in September (they jumped out at night, so I had to go check for carp in our garden every morning), so with hundreds of small fry I got a bass to clean the business up, by the end of summer I had to start feeding him because he ate everything he could. The next summer it was crazy warm and I wanted to swim but the green water didn't look to appealing and I had a week long mission redoing the swimming pool.
I caught the carp with a bamboo and line, walked around the pool to tire them out, tested my hook-less lures on the bass, was great but will never do it again, very expensive experiment.