you should try hand feeding them and make them accustomed to feeding in low light, to get them used to you. Very personable fish any time I come in the room my guy comes out. Never had a problem with the growing maybe ur not seeing it cause you see them everyday. Nightcrawlers, meal worms, snails and there have been times when I'm in a pinch that he's eaten ground beef (not sure how healthy that is) mine won't eat any dried foods, probably cause he's spoiled. He won't eat any fish or shrimp either but I do hear that most also enjoy silver sides and brine shrimp