I'm about to start cycling a 75 gallon aquarium for my common goldfish. He's grown about an inch and a half-ish since I got him 2 months ago (he started about 1.5 inches, now he's about 2.5-3 inches), currently in an unheated 29 gallon tank. I've read conflicting information regarding goldfish growth and temperatures, so I'm just curious: 1. Do they NEED warmer temperatures to grow after a certain point, or do the warmer temperatures just help with growth? The tank is currently sitting at room temperature, which fluctuates anywhere from 69-72 degrees. 2. If I get a heater, what temperature should I raise the tank to? 3. How many watts should I use in a 75 gallon tank? I'd like to use 2 heaters instead of 1.