These guys are my babies in the store! They are very shy and inquisitive but go into alligator-mode when you throw in a feeder.
They love to weasel around in the holes in rocks. I’ve seen tanks online before where someone had a tank with a rock wall along the back, with a network of pvc pipes hidden inside it so the eel could peek out of the holes.
Word of warning though: identify and research the specific species you’re getting. A few species stay small enough for a community, but most grow to be multiple feet long, which is why I haven’t gotten one myself. And they grow in all dimensions too— not just length. Even within the same aquarium trade name—like spiny eel, tiretrack eel, fire eel; there can be multiple species sold with the same name where some stay small and some don’t.