He is cool! If you had a bigger tank I would suggest looking into a snowflake eel, they really only mess with things smaller than them. But not sure if the octopus would mess with him, maybe others could weigh in on that. But Like I said you would at lease need a 70 gallon for the eel and octopus
Not to be rude, but PLEASE don't do this. Eels are the natural predators of octopuses, the octopus will be eaten within minutes, if not sooner. Octopuses can not and should not be kept with fish of any kind. Anything smaller than them they will eat, and anything bigger than the octopus will harass or eat it. With how smart octopuses are, to keep them with anything that will attack them is a terrible thing.
This is an article about octopus cohabitation which you should read @Rawsreef . I suggest you ask any questions on the forum there. It's pretty slow, but the advice you will receive will be correct.
Post # 10 on this second thread has a list of what animals have been successfully housed with an octopus. As you will see, it's a short list. Octopuses are creatures which require a tank set up around them.
@littlefoxx , don't give advice about things which you have done no research for. A three second google search would have found that eels eat octopuses. And, might I add, it could have also revealed that carpet anemones eat fish and that you need to quarantine sensitive species (like regal angelfish). Please do more research into things before you try to advise others. Thank you!

