Somebody dropped a Gummy Bear in my tank!!! (or actually, Frogfish advice needed!)

[Delphinus]

A butterfly of all things

I don't see why a smaller tank like a 10g or 20g couldn't work for the time being. I think the max size of these guys are around 10-15cm, so eventually he'd probably need to move on up, but if your guy is only 1" it seems to me he'd fit fine in a nano for the time being. (It will be easier to target feed him in a nano too...)