Octopus mercatoris


This is the newest member of my ever growing creature collection. A pygmy species from the Florida/Carribean area. He's been here for about a month now and is finally getting comfortable enough to come out for extended periods. Really cool little guy. A shame they don't live longer. Sorry for the bad pics. I don't have a macro function on my camera.


That is so cool! How big is his tank? What does he eat? How long do they live?
lol, sorry for all the questions :)


fantastic, i hoping that when i eventually finish with my 19 gallon QT that i will make it a home for a pygmy species of octupus that inhabits parts of Western Australia. LFS has one and its fantastic, only live for upto 2 years though.


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Yea, where'd u get yers from? Ill bet that I can keep one, and it would be cool. Not as sweet as the blue rings, but then again, not as deadly neither!!:D Wat do u feed it as well?


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Nice octo! Just out of curiousity, can you say a little more about this setup (size, filtration, lighting, how the tank is sealed)? Is it safe to assume that there are no other tank mates?
Originally posted by Magic_Carp
iv seen a video that had some guys octo come out of the tank, crawl up the dresser and steal a gold fish from a FW tank and when back to the tank, it was our of the water for like 5 minutes, i love those guys!

Is this video online anywhere?


That video is a re-enactment.
Okay to try and answer the questions. I paid $25 for him and had him shipped from Florida but I'm afraid I can't say more because the seller is a competitor of this fine website :) . The tank is a 12 gallon JBJ NanoCube that has been fallow for a couple of months after I had a heater malfunction and cooked my seahorse and some of his buddies. I did some research and found that O. mercatoris does well in a tank this size as does O. joubini although they are harder to come by.
I pulled all the filter media out of the back of the tank and added LR rubble in poly mesh bags and I run ChemiPure back there also in case he inks. Lighting is standard and even though he's nocturnal he's gotten used to the lights and comes out fairly often.
I feed him fiddler crabs and the occasional emerald crab for a treat. Amazingly I added two chromis to the tank and he ate one immediatley and the other is still alive after 2 weeks! I do however see the octopus stalking him sometimes. Don't know if it's just playing or he just can't catch the little guy.
So far I haven't proofed the tank as he doesn't show any interest in leaving but he does climb in the back filtration area sometimes but comes out if I open the lid and lift the LR bag he's hiding under. I think he goes back there to eat amphipods as there are literally hundreds in this little tank from sitting with nothing in it for a long time except for 16 lbs of LR.
Thanks for your interest everyone. More pictures soon.


Tankmates really aren't a good idea as most things eat or are eaten by cephalopods. I can't believe that chromis is still alive and I'm sure it's just a matter of time


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very cool. It will be interesting to see how smart he gets in trying to test the exits. :nervous:
more pics when you get them :yes: