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Octopus tank mates


Colossal Squid
Nov 19, 2002
Corals are typically not a great idea, most require much higher light levels than an octopus. There are a few low light coral species, but you have to be careful about stings as octopus skin is quite sensitive, also octopus like to rearrange their environment, so the free living corals like Mushrooms may get slammed!

Octopus really do best in a species tank, with some clean up crew (although crabs generally end up as dinner :biggrin2: ). We keep giant seven armed stars (Astrostole scabra and Kina (NZ sea urchin Evechinus chloroticus) in with ours. Occasionally we may add a greenlip mussel line (from a farm Perna canaliculus, interestingly the octopus doesn't touch this, stars love it tho' :biggrin2: ), we also have various macroalga's in the tank. Very occasionally we have spotted wrasse (Pseudolabris celidotus) in the tank, but fish are not usually recommended (either end up as octodinner or annoy the octo). All of these are NZ species, but I'm sure there are similar in your neck of the woods. Oh and we have a very large tank (1200L) for these, they're all pretty big (even the octopus!)



Jan 19, 2004
leather or soft corals often require less light and don't sting like rock corals or anemones. (they are also less sensitive than rock corals)

however I haven't tried them with an octo yet. used to have anemones, but one time I ended up with a dead octo entangled in one of those.

brittle stars and starfish in general do quite well. I my tank, shrimp also did great, allthough this doesn't always seem the case.

as jean implies, the bigger the tank, the more chance of success. allthough I'd never recommend fish in an octo tank for reasons in previous posts.

Michael Roth

Blue Ring
Jan 19, 2007
I use a rock with several christmas tree worms, a couple VERY small anemones, and it is truly amazing watching mine hunt chromis every month or so. The hermit crabs, he doesn't seem to want to eat, just throw them around the tank for fun.


Blue Ring
Apr 25, 2007
Do Not!! I repeat Do Not put a chocolate chip starfish in with them!! I lost an adult blue ring and a juvenile o.vulgaris (in 2 seperate tanks) to these assassins! The blue ring was cornered in a piece of live rock an eaten alive!! My friend witnessed this while I was out of town. I have had success with a coral banded shrimp in my 30gal cube along with a sub adult bimac; a juvenile mimic; a long spined sea urchin and a maroon clown. The octos chase each other at times, but never get into any altercations. I also have a 14gal biocube with a blue ring; a smile spined urchin; a blue damsel; several blue legged hermits (occasionally get eaten!) and several small nasarius snails.

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