Yes....North American cats,coldwater species.
Food includes Pellets,worms,small frozen fish etc etc,flakes not very substantial,these cats grow to 4 feet in nature,2.5 is not uncommon in captivity.
had one at 25in before the weight of the snow ontop of the ice in our pond forced all the underneath water out and he died... he was a bute... he ate flake until he was 6in then feeders and guppies then pellets, frozen smelt, chiken, hotdogs, mac n cheese... whatever was in the tank including my fidler crab
I never had a problem getting mine to eat anything. As for water. Anything will do. I had to keep mine in a 100gal while I was replacing the pond when he was about 2ft. Went on vaca for a week during which the power went out. When I checked it ammonia was so high it was way off the scale and he was fine.