anyone know about these guys in aquariums? i saw one for sale recently and would really like to look into them for a future home octo. thanks!

Those octopuses labelled "joubini" are usually the dwarf "mercatoris". We have several people keeping mercatoris - search for mercatoris to find them all. Einey (Einstein), Animal Mother's octopus, was a mercatoris. Lev has a thread about his efforts at raising mercatoris babies.

Nancy

http://tropicaloceanreef.com/store/product_info.php?products_id=525&osCsid=6c0ee76806a9cc965082c9c9f0ddb288

This doesn't give much info, but you can buy it here, and it's care requirements should be the same as other octos. Remember, it is small.

I have kept quite a few O. mercatoris and reared several clutches. Frankly, as aquarium species, they are pretty dull. They remain tightly holed up during the day and only come out at night. They are shy and not interactive. And you will have an adult for only a few weeks. However, rearing the hatchlings is interesting and doable.

Roy

What is the difference between mercatoris and joubini, in addition to the size of the eggs?

The photo in the link below, if it is really joubini, suggests a bluish color similar to briareus, but previous photos I've seen don't show this at all.

Nancy