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what can go in a tank with an octopus


Apr 10, 2007
has anyone had any experiance with keeping fish with there own "defences" in tanks with octopus, for example, a fish that was poisonis like a lion or scorpion fish, would the octo no not to try to eat it? Also, if there was a porcupine fish, would that maybe be ok because of its ability to expand? i was also thinking that moray eals might work because most octopus would be to large for the eals to eat and i think that it would be hard for an octopus to ealt an eal because of its size. id realy like to no what you think about this
good luck! there are people here who tried a pterois with their octo.
didn't work. octo had a good meal though.

as for porcupine fish. I assume you mean diodon ssp. these guys crack shells! I don't think they have a problem with ripping octo limbs. I have experience with them, they're rather agressive fish.

moray eels? these are an octo's natural enemies. even if they are to small to be of hazard to your octo, you're creating a stressfull environment since they cannot escape eachother.

basically. nothing goes with an octo either a fish is to agressive and will harass your octo, or it ends up serving as a good meal. there are success stories, but they are the exception, not the rule.
Correct ! Absolutely nothing is the best, other than some serpent stars for cleanup.
One member tried keeping seahorses a few years back. Expensive food.

Octopus are mostly shy animals, and will stress out with tank mates, leading to infections, problems, and a premature death.
:welcome: fellow Pittsburgher! You can keep a clean up crew, like hermits and snails, but they may become lunch for the octopus. While it is an interesting idea, I have to agree with dragonfish. Two things happen with fish and octopus, the fish eats or harms the octopus, or the octopus eats the fish. Either way, you won't be happy.
I think your best bet would be to get another tank for fish. Besides, expetially with my octo, he's be preaty territorial anyway. He doesn't like me putting in new things in his tank. He tries turn things over and constantly moves them till I take them out.

Kraken(my octo) says "MY ROOM, GO GET YOUR OWN AND PUT THINGS IN IT!!!"
ive had some good luck with fish that are very docile yet fast that hang out in the upper water columns like cardnal fish and cromis... mostly these just provide the octo with some entertainment and he will never catch them. the octo i have now has a single pj cardinal with him that they actually play tag. the fish evades the octo for some time then when the octo does touch it he doesnt try to catch it then they seperate and do it again. ive also had luck with very small blennies and gobies that would normally be to small of a meal for the octo and way too fast. they also make good clean up crews. ive got an eyelash blenny in the octo tank now also and he hangs out in the mouth of the octo den picking off scraps but never attacks any legs or anything. basically if youre gonna put something in with the octo A) make sure its cheap B) make sure its fast C) and make sure its extremely docile D) and make sure its fairly small compaired to the octo
I wouldn't call chromis or any other damsel docile. they can be fiercely territorial in my experience. or maybe I just saw the damsel from hell :wink:

anyway if you really do want fish with your octo: this is sane advice:

basically if youre gonna put something in with the octo A) make sure its cheap B) make sure its fast C) and make sure its extremely docile D) and make sure its fairly small compaired to the octo

and I would only add a E) be prepared for disappointment (that way, you're all the happier if it does work out.

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