lots of people keep them in 300G stock tank and the fish seem ok about it, just do a lot of WC and it will be just as happy to see you like a dog, but IMO it is not the right thing to do!I know quite a few people that keep rtc's in 300 gallon stock ponds. You should be fine. On average they grow 3 feet and live 8 years. And if u give them minimal food(yet enough to be ok) the most likely size is 30". 4' is what they get in the wild or massive ponds. It sounds to me like you have a good pond size. Of coarse everyone has their own opinions.
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