yeah, those are definitely goldfish, i used to be a big koi fan, the JD has been with goldfish for over a year since he was about 5" or so, he became very tame after the female JD died so he was lonely and i decided to put him with some goldfish to see if it would work and it does very well, ammonia has never been a problem, he is actually much happier with goldfish than with other cichlids, the 5 large goldfish were already medium - large when i got them, only one of the goldfish in there has been partially raised with the JD