[Marian Nichols]

Although goldfish are cold water fish, and we do not put heaters in the tank, they are inside a home, thus the tanks usually are only a few degrees below room tempertures, and most of us keep the fancy goldfish which really do require warmer water than the common goldfish, like comets. I once kept a betta, a tropical freshwater fish in my goldfish tanks for a couple of years, which you aren't suppose to do, he did great and rule the tank. He never actually harm the goldfish but he love to chase them. I didn't do that deliberately, just happen the fish was without a home and that was the only tank I had set up at the time.