You need to give these fish a lot more than just worms, as macrobrachium and neocaridina shrimp are their main diet in the wild, so giving them that will get them to grow fast, once they settle and start eating a proper diet their growth is quite fast and they also get tame.
Not much. Moved it into my 150g for more space and to break down his grow-out tank. Hadn't seen it in a while, but just saw his head pop out from driftwood during this past Monday's water change, so it's still surviving somehow...
When he wanted to eat in the 20g grow out, he would swim to the top and take worms from my son's hand. Only thing I can surmise at this point is the eel just isn't a big eater and will take a longer time to grow up.
