• Looking to buy a cephalopod? Check out Tomh's Cephs Forum, and this post in particular shares important info about our policies as it relates to responsible ceph-keeping.

Not so dumb question


Aug 18, 2009
Has anybody here tried to keep a small octopuss and a big seahorse in the same tank?

I have a feeling that if it is well fed, the seahorse wont be under any danger. But my feeling is just a feeling and people here can have the last word on this matter.

Its a 80 galon tank, its would fit one octopuss and a couple of seahorses.

From my very limited experience I have successfully kept a ribbon eel, small cuttle and my octo for over 6 months without issue (along with 2 large hermits and lots of fish, snails, crabs, etc).

I can say with 99% certainty that the ribbon eel and octo are truly not an issue to each other and seem to not mind sharing housing.

I have also never seen any problem with my cuttle and the octo. They seem to completely ignore each other.

I keep my tank well stocked with shrimp and small fish. I also offer frozen fish and shrimp daily.

For a seahorse its a tough call I think as they are increadibly delicate (I have tried to keep them before). It is more likely that something else will hurt them (fish, pumps, water flow, etc) then the octo.
For the most part, cephalopods should be kept in a species only tank. When you visit a public aquarium, you will notice that most octopus are in their own exhibit with maybe a sea star or urchin in the exhibit. Most cuttlefish are also kept alone in an exhibit with only other cuttlefish. It is not a good idea to mix fish and cephalopods, it almost always ends badly for one of the animals.

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