Around 86 inches in length, 26 inches width and 20 inches in depth.Bichirs and gar come to mind. What size is the tank?
True, they just need some comfy and safe space to hide in.Fire Eels don’t dig up roots as long as you have some pipes of long caves.
Hmph, interesting. They might nip a bit, but they won't exterminate them all. Too bad I already have a few.maybe a pearl gourami