Ive heard that about bristles, however my yellow eye white tail bristle has an absolute obsession. Dude pecks the rocks all day, everyday. If hes moving its to go peck a rock.The bristletooth tang I had stuffed itself with frozen and practically nothing else . My foxy is largely the same but I do feed frozen food for herbivores and a few times a week feed spirulina gut stuffed frozen brine as well