They don't do well mainly because of difficulty in feeding. You already have yours eating so that's good, feeding them can be frustrating and tedious. I've found they are pretty delicate to feed, not like my jeweled. I slice thin strips about the width of the end of his nose. Every thing I slice into strips really no longer than 3", squid, silversides, squid tenacles, shrimp, silverfish. Variety is good, even a little vit soak; I feed every 2-3 days. I find him to be a bit timid to feed and I will let the food go just as I get it to his face, and then he chases it down. In 4 months he's doubled in length and thickness. They are an enjoyable addition if you will have the patience to baby him when it comes to feeding.