Eels are good with larger fish like Tangs, Butterflyfish (most are hard to care for though), large Angels etc. I believe that the general rule of thumb is just to make sure it can't fit into the eels mouth. However, everything mentioned above can also depend on the kind of eel. I think the fish above with a Snowflake would probably be alright, however, I think some more aggressive/larger kinds of eels should not be kept with the above fish.
[CENTER]Please don't forget about the toxins in some corals (like zoas and palythoas)
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