I have 2 baby arowanas about 2 inches. One of them beat the crap out of the other one. I didn't think this would happen this early but it did so i separated them. I wasnt expecting this so when i separated them, one tank doesn't have a heater just a filter. I wanted to know how long it would last in there without a heater. Also how long will it take for the one that got beat up to heal?