I have always wanted a salty with a tiny octopus, you have reawakened my hunger, lol.
You CAN keep an octopus if you do lots of homework first and take the time to learn up front, before you jump in. 98 percent of the people that keep octopus did not catch them, and don't live near the ocean. To learn how to do this go to
www.tonmo.com and study up. There's even a book out now about how to keep octopuses. I recommend the species "O. Hummelincki" because they are similar to a bimac in personality, but you don't need a chiller (expensive) and they are a little smaller, so can be kept in a smaller tank. You can buy one online! (but do lots of learning and prep first!)
That's an AMAZING tank!!! I remember reading that octopi kept in captivity are very difficult to care for and rarely live for more than a few months. You're obviously doing a fantastic job by her
Octopusses are similar to salmon in that their natural life cycle is to breed, and then die. Their natural life span is only about a year (6 months to two years, depending on species). If you do your home work you probably won't kill an octopus, but it will die within 12 to 18 months even if you do everything right.
Full disclosure: Lefty laid (infertile) eggs in January, tended them for four months, refusing food all the while, as is normal, and died about two weeks ago. I'm trying to decide if I should go look for another young bimac, or collect some other, local animals. Octopusses like to move rocks and shells around, and the strawberry anemony got pretty beat up.