Contemplating Octo Tank


New member
I've been thinking for a while now of setting up an octo tank. I've been thinking about getting pygmy octopuses, which from what I have been reading, are usually listed as O. joubini, but are actually O. mercatoris. What I've read suggests that they can be kept in small groups comfortably. The problem is, I don't know if that information refers to true O. joubini or O. mercatoris (or both?). Does anyone know?

If they can be kept in groups, I was thinking of setting up a tank that could house 6 total. What I don't know is what size would be best suited for 6
O. mercatoris? My goal is to create a population I can sustain since they don't live long, but produce large eggs with benthic larvae.

Also, would then take to pvc tube dens? I was thinking of making my own aragocrete rocks with pvc tubes imbedded in it for dens. Maybe some cut in half up against the glass for viewing.

And finally, the supplier I found can get them for me in spring and in fall. When would it be better to get them? One of the posts I just read said that they're breeding now. So if I wanted to get animals with the most time left, would fall be better?
Hi. I currently have a mother mercatoris right now. She was introduced to my tank in mid January, and I just noticed the eggs (there are about 50 of them) on march 16th. I am not knowledgable about keeping multiple octos in one tank, but I would guess that to house 6 you would need a very very large tank. Yes they will definitly house themselves in PVC pipes. I have been told that joubini lives in deeper water, so if you buy a pygmy octopus there is a greater chance of getting mercatoris than joubini
My recommendation would be to set up a tank just for one octopus. Let it cycle for 3-6 months and then order a O.bimaculoides for your first octopus.