Keeping an Octopus in a home saltwater aquarium.

I have kept brown and even poisonous blue ring (I do not recommend Blue ring) octopii.
In fact a brown octopus was one of my first saltwater creatures back in the mid 1970s.
They make great pets and are highly intelligent, in fact mine would recognize me and come to the top and stick its tentacles out to take food directly from me.

Here are a few points to keep in mind though:
*An Octopus will squirt ink they squirt when frightened, but that is rare. Try and keep a peaceful environment and this will not become a problem.

*The Blue Ring Octopus from the Great Barrier Reef is one of the most toxic animals on earth with its neurotoxin. A bite can kill in under an hour (although they very rarely bite).
These Octopus prefer the warmer waters that most home aquariums provide however the poison problem I think over rides this plus (even though I have kept them).



Here are some important points for success in keeping a Brown Octopus vulgaris and bimaculoides:
*They are cold water preferring so an aquarium under 75 F is best (under 70 F is better).

*They need crab or other crustaceans in their diet. Along this line they will consume cleaner shrimp, coral banded shrimp and similar

*They are sensitive to nitrates above 20 ppm. So good filtration (such as the Berlin Method which includes live rock and possibly a Mud Filter is a must). Along the line of anecdotal comments I have read statements that a Protein skimmer is a must; not true! (Although the use of a Protein Skimmer certainly helps keep the odds of a healthy aquarium in yours and your octopus' favor). I have kept many a healthy Brown Octopus without a protein skimmer, the key is low nitrates and a healthy environment (which includes Redox Potential) and if a Protein Skimmer is part of this plan, fine, however there are other good methods as well. If anything the benefits obtained by a UV Sterilizer (although different benefits) would be more important.

*They have short life spans, often under two years and a warm aquarium will shorten this further. Also do shorten it further by easily escaped from loose fitting tops.

*They do NOT mix with eels (mortal enemies)

For further reading about Octopus intelligence, please read this article from the Washington Post:
Brilliant Houdinis of the Deep