Scientific Name: Octopus joubini
Reef Compatibility: No
Minimum Tank Size: 10 gal
Max Size: 5½"
The Dwarf Octopus is also known as the Atlantic Pygmy Octopus, and is covered with chromatophores that allow it to change colors quickly to mimic its surroundings. Unlike most animals, the Octopus has a rectangular pupil. It usually comes out at dusk to feed on small invertebrates or small sleeping fish. It uses its eight tentacles to bring the catch to its beak-like mouth. Of its total length, the arms will represent about 70%, with the mantle comprising the rest.
The Octopus will do best in an aquarium if provided with plenty of live rock and ample hiding places and a large area in which to move. It prefers an aquarium with caves and medium to coarse substrate with low lighting levels. The ideal lighting for this aquarium is dim actinic lighting.
The Octopus can be surprisingly strong, so in the home aquarium, it is best to anchor the rocks, or even glue them together to keep the Octopus from toppling the rocks into the glass or onto itself. Cover all tank openings very well or it will try to escape. The Octopus is sensitive to high levels of nitrates and phosphates, as well as any copper-based medications. It its best to maintain the Atlantic Pygmy Octopus in a species only aquarium with some live rock to aid in water stability.
Always approach the Octopus slowly to avoid causing it to release its ink cloud in defense. In the aquarium, this release of ink will necessitate a large water change to avoid its death.
The Octopus can be fed small live feeder shrimp or freshwater ghost shrimp, small crabs or hermit crabs. Any live foods should be fed spirulina based dry foods, plankton, and cyclops to enhance their nutritional value.