Need to build a new home for a snowflake eel

[photopilot]

We just got an established but thinly stocked a 24G reef tank. Among its members is a small snowflake eel. He is tiny and i though harmless but we have lost a goby and firefish in the last week, so I guess he is not that tiny. We would like to set up a tank for him. We have a 10 gallon hospital tank we can put him in temporarily. What is a reasonable size tank to hold him in that can also fit a few other fish? I have access to a 40G cube and a 40 tall right now, just not sure either would be big enough for an eel and a few other fish.
Here are fish I'd like to see in there
Triggers
Puffers
cowfish
angels
Would it be even worth starting a 40 gallon tank for a small eel? What else could I get into a 40 gallon tank that won't compete or get eaten by him?
Thanks for any Suggestions
PP

 

[saxman]

You'll want at least a 4 foot tank for a SFE (such as a std 55 or 60 gal).
As for the other fish...you could keep a dwarf angel, or a toby, but for cowfish and triggers, you're looking at a 100 gal or larger, depending on species.