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Apr 12, 2008
im sure there is an old thread about this, but im going to ask anyways.

i already have a saltwater tank, just a 10gal, with wayyyyy too many fish. in the tank i have a blue damsel, an oc. clown, a 6line wrasse. these three are all a bit less than 1 1/2 inches. i also have a small snoflake moray eel that is about 8 inches long, and a worm goby that is about 2 1/4 inches. im cycling a bigger tank rite now, and i had inteded it for an octo, but then i decided on a huge reef tank...but its too pricy for a 17 year old. my question is, are any of my current fish able to be tankmates with an octo? i know the eel probably isnt, i heard eels like to eat octos in the wild. but what about the damsel and clown and wrasse and goby? they will all grow to about 4 inches, except the goby, which gets up t a foot.

anyone have any luck with a small octo and unaggressive fish like mine?


Staff member
Nov 20, 2002
You're right about the eel, but also, those are not unagressive fish. Better plan to clear your tank of fish before getting an octopus.

I'm not clear whether you're keeping the 10 gallon or getting a larger tank - 10 gallons is way too small, but then you don't need a huge tank like you were planning at first.

Sep 8, 2006
It's pretty standard advice to avoid mixing fish with octos.

Clowns and Damsels are generally very bold and territorial despite their size. I know a few reefers who have scars on their fingers/hands/arms to prove it. The wrasse could go either way. Here's what happens when you mix snowflake eels with octos. http://www.youtube.com/watch?v=d5naQT0xJq0