I recently acquired two octopus, which I believe to be Briareus. They are kept in separate, but identical enclosures, sharing filtration, lighting, etc. One of the octo's is behaving what I would assume is normal - hiding in a cave all day. The other octo however, after going into the rock this morning, is now down on the bottom, with his legs wrapped around his head - with no interest in the rock it seems. Ideas? Concerns?