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briareus vs. bimaculoides


Mar 20, 2009
what are the main differnces in care for these guys? Size, temp, nocturnal/diurnal, desire to escape, etc.

I've always thought that Bimacs were the best aquarium octopus, but it seems a lot of people are now getting briareus and I was just wondering about them.
The main reason more people are getting briareus is because they are more readily available than bimacs. Also bimacs require slighlty colder temperatures so you might need a chiller to keep it. I have never kept a bimac but i have kept briareus and i would say in terms of interaction and such the bimac is probably better since it is naturally diurnal while the briareus comes out more at night, although they can adapt and become active earlier. Also, the bimac is generally smaller than a briareus since it doesnt have the long arms that the briareus has.
Hope that helps. :smile:
Just wondering what sources have you found for bimacs?
I highly doubt those are bimacs. The pic they supplied is almost definitely not a bimac. Also, they most likely collect them from the atlantic or gulf and not the pacific. I would guess these are humellinckis (which also have two eye spots like bimacs). Either way both bimacs and hummelinkis make great pets.
Ok thanks. I don't actually have a source for bimacs (unless I get one for work then I go to a scientific supplier), I was just curious so I can plan for the future.
Well. i get my octo from reefscavengers tomorrow, so if you check back tomorrow you can see what their "bimac" actually is. Hopefully it is a hummelinkci and not a nocturnal octo.
They are similar in that they are diurnal and also dont get very large. Bimacs require colder temperatures though, meaning that you would probably need a chiller or if not a lot of fans to cool your water. Hummelinckis are from Florida so they require tropical temperature in the upper 70's; meaning you wont need a chiller (which is a good thing). I've never kept either but both of them seem to make good pets.
Check out the journals section, many have the species listed in the title and you can get a feel for the different octopuses in captivity. Most of us that have kept hummelincki nalme them as favorite because they interact so very quickly with humans. The links below are my journals for Octane and OhToo:


I keep a tank available for a hummelincki if (as now) there is not one in residence even if I have other octos (currently a nocturnal macropus and a very shy briareus).
I've kept a bimac for almost a year, and I've never kept any other octopus. I'm a diver, in Southern California, and it was important to me to keep local animals that I caught myself, so I needed a chiller, and only a bimac would do. However, after learning about hummelincki on Tonmo, and seeing pictures, I would get a hummelincki if I just wanted an octopus and didn't care specifically about keeping So Cal animals. It seems to me that keeping a hummelincki would be like keeping a bimac, but without the expense, and threat of equipment failure that comes with a chiller. Plus I think that a hummelincki is just a little bit more beautiful.