Thought id share a pretty unique experience. I had a school of tetras in my tank, and decided i wanted to upgrade to some predatory catfish, i put in a RTC/TSN hybrid that was 1 foot long, he whiped out all the tetras except for one, they co-existed for a month until i sold the catfish, i than put in a perrunno and a RTC (both as babies), they grew together for 3-4 months, leaving the tetra alone, the tetra was also housed with 2 limas and a 8 inch 2 line PIM. No catfish, is able to eat him, he is either too smart, or hides at night, he has spent 6 months, alone in a tank with catfish, and has yet to be eaten. Why?