Mine does NOT tolerate other ATF. They end up in pieces every time. I've given up on that. He does however do well with my tarpon and pink tailed chalceus. I get false charges and a few missing scales every now and then but never the true killer aggression I get when another ATF is in there with him. Some GATF do well with other ATF, but mine does not. He ignores catfish and plecos though.