Whether or not they need a heater depends on the temp of the room the tank is in. Low 70s for a water temp is fine, up to the low 80s. They don't stay 1" very long and absolutely positively will not "grow to the size of the tank'! You'll need at least a 75 gal tank to keep it long term. Oh and adult Softshells are the perfect gift for a kid who has 6 fingers on each hand, seeing as he has a few spares. The beak is anything but soft and they're not shy about using it!