haha i bought a few feeder goldfish about a year and a half ago, i used them to help set my tank up since they can be put in cold and warm water, i put them in whilst the water was still cold and put the heaters on to bring the water temp up all the while my goldfish were cycling my tank. guess what??-- 2 of my goldfish are still with me!! they are pretty much the same size as my green terror and everything leaves them alone. they do have scales missing now but i love them, they are like arnold schwarzer-fish, hard as nails!!!