[Delphinus]

Anything that fits in their mouth is fair game. I have one that is 8" (on the small side even for this species) and have a smallish orchid dottyback in with him, who wouldn't be able to fit in his mouth. I got totally lucky in that (at least so far), this eel has ZERO interest in eating fish (when I offer silversides or even just pieces of silversides, he comes up, sniffs it, and then swims away. Whereas mysis, krill, squid, and shellfish, are gone instantly.) So there is definitely some individuality with these guys, which is the same as to say "might be OK, might not be OK, only way to tell what you'll get is to try." Sorry for the wishywashiness, but it just seems to be that way. What works for one person won't for another. Thus realistically the most diligent option is err on the side of caution. If the tankmates were the really tiny "nano" type gobies, I personally wouldn't chance it.