when I first got my rtc, i put him in my simplistic 37 g set up. No heaters. at 68 F he did quite well and grew about 3 inches in 5 months. I moved him over to the 110 g at 78F and he doubled in a month. worst part, is he recently learned that he is the biggest fish in the tank. now everytime he smells food he eats everything and I have a hard time even hand feeding the other fish