That depends on a few factors, size of tank, type of morays, size of morays, temperment of the eels. You will need a real large tank depending on the eels. Some eels will get along fine with others. Hara has an eel only tank with 3 in there. 2 Yellow Heads and a Snoflake (i think). I myself have an eel that will not tolerate another eel in the tank with him. He will try his best to kill it. You will have to give it a try and see what happens...just keep a close eye on them. Let us know how it works out.
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