Guide to Keeping a Pet Octopus: Care, Legality, & Enrichment

Experienced enthusiasts find the octopus to be a fun species to keep in a dedicated aquarium setup, though they do require a high level of care.

Updated June 6, 2023
Octopus Swimming In Aquarium

Keeping an octopus as a pet has become more common as interest in new and varied aquarium creatures and setups increases. Their popularity has grown since the tank creation of comedian Tracy Morgan's octopus was featured on the television show Tanked. These fascinating creatures have very specific care needs and are not the best choice for novice fishkeepers.

Octopus Facts

Octopuses are invertebrate animals in the scientific order Octopoda. The octopus does not have a spine or skeleton, and their skin is soft. The only part of their body that is not soft is their beak, which is found at the base of their tentacles.

These tentacles are actually arms which are covered with suction cups and about 66% of the neurons for an octopus are located in their arms. This allows them to use their arms to sense their environment and explore, and they can even "taste" using the suction cups on their arms. They also have three hearts. Their blue blood is high in hemocyanin, a protein that contains copper, unlike hemoglobin (which we have in our blood) that contains iron.

Legality of Owning an Octopus

There are more than 300 species of octopuses, and thankfully none of them are on the endangered species list. There are currently no laws regarding keeping a pet octopus and you don't need a permit in any states. However, you may have trouble keeping one if you live in an apartment or condominium. Many buildings have strict rules about tank size and you cannot keep them in a small tank.

Is Keeping an Octopus Ethical?

Ultimately, this is a question you have to answer for yourself. If you are an experienced aquarist and you know how to meet an octopus's physical needs and can keep them active, you can probably keep one in good condition.

There are many examples of aquarists with the required skills keeping octopuses happy and healthy in private aquarium settings. But understand that octopuses are highly intelligent, and they need mental stimulation to be happy in captivity. If you aren't ready to make sure their setup is secure, they get the proper diet, or offer them interesting activities to keep them occupied, you should opt for another pet.

What Species of Octopus Are Kept as Pets?

Many species of octopus are unsuitable as pets, either due to their size or the fact that they can be toxic to humans. For example, the blue-ringed octopus emits a dangerous venom when it bites that cannot be cured. There are a few species of octopus that are safe and commonly sold as pets. These include:

  • Algae octopus: The algae octopus can live in a tank that is a minimum of 50 gallons. It's known for being active, even during the day when other species are more likely to hide. The algae octopus needs an average water temperature of 78 degrees Fahrenheit.
  • Atlantic pygmy octopus: This is one of the smallest species and they will grow to about 5½ inches long (3 inches of which will be their arms). They are a good choice for a beginner as they have the smallest tank size needs. They need to have excellent hiding spots, as they can be shy. They also have been observed playing and can be a fun octopus to watch.
  • California two-spot octopus: One of the most popular pet octopus species, it has arms that can grow as long as 23 inches, with a mantle up to 7 inches. The minimum tank size for this octopus is 50 gallons. This species is also called the bimac. They require a water temperature of around 59 to 72 degrees Fahrenheit. They are thought to be one of the "friendlier" types of octopus that are kept as pets.
  • Caribbean dwarf octopus: This is a smaller octopus that can live in a 30-gallon tank. This species has a short lifespan in captivity of about 8 to 10 months. They require a tank that has water around 74 to 76 degrees Fahrenheit.
  • Caribbean reef octopus: The Caribbean reef needs a tank of at least 50 to 75 gallons with an average water temperature of 78 degrees Fahrenheit. This is another species considered friendly and suitable as a pet.
  • Common octopus: These can be as small as 12 inches long or as big as 24 to 36 inches. It will need a tank that is a minimum of 50 gallons. This species has been used most often by researchers.
  • East Pacific red octopus or ruby octopus: They are on the small side and can live in a smaller aquarium. An adult will weigh around 5 ounces and will be about 20 inches long overall. Since they come from the colder waters of the Pacific, they need an average water temperature of around 60 to 65 degrees Fahrenheit.
Need to Know

Keeping an octopus as a pet should not be taken lightly. Only experienced aquarium enthusiasts should take on this venture.

Danger: Don't Keep Blue-Ringed Octopuses

Dangerous blue-ringed octopus.

Blue-ringed octopuses (Hapalochlaena spp.) are native to the Pacific and Indian oceans. There are four species in the genus, and all are extremely toxic. In fact, the venom from their bite can kill within minutes.

Even though they are beautiful, and have occasionally appeared in the aquarium trade (though they are relatively rare in the modern hobby), they are not safe to keep and are not good candidates for home aquaria. Yes, they are striking, but if you see one for sale somewhere, be aware that these species are potentially very dangerous.

Fast Fact

Even though they are small, each blue-ringed octopus carries enough toxin to kill around 25 adult humans.

Care of a Pet Octopus

Caring for a pet octopus requires a weekly time commitment and can be expensive. Although they're fascinating creatures, take time to research their needs before getting a pet octopus.

Proper Tank Set-Up for a Pet Octopus

Octopuses live in reefs in the wild and need a tank with liverock that simulates that environment. They are nocturnal and need to have a tank with formations where they can hide during the daytime. In addition to liverock, they like large shells or PVC pipes to hide in. They are also very strong and can move rocks and other hiding items around, so make sure your setup is very secure before adding your octopus.

Because the octopus has a high metabolism, they need to have a high oxygen content in their water. They also need strong filtration as they are messy eaters and shed their skin often into the water. A high-quality protein skimmer will help keep the water clean and well oxygenated.

Octopus Tank Lighting

Do not use any harsh lighting in the tank and keep it away from sunlight. Octopuses prefer to live in the dark and will tolerate a weak light on during the day and no light in the evenings.

Toxicity Issues in an Octopus Tank

Make sure your tank does not have any copper in it anywhere (copper piping is out). It is toxic and will leach into the water column, and can kill your octopus.

Water in an Octopus Tank

Your tank temperature will vary based on the species. The pH should be about 8.2 and the ammonia and nitrite at zero.

If these levels are off, they can easily make your octopus ill or kill it. Because they are so sensitive to the water quality, you must also cycle your tank for at least three months prior to adding your octopus.

Quick Tip

You should regularly test salinity, and the water's specific gravity should be around 1.022 to 1.023.

The Octopus Escape Artist

Because the majority of their body is soft, they can squeeze through some incredibly small openings, and their arms are strong enough to push open a tank lid and escape. Because of this, you need to make sure your aquarium lid is tightly secured and there are no openings they can break out through.

Some octopus keepers have Astro turf or velcro along the top of their tanks as the scratchy feeling is a deterrent for octopus arms reaching to the lid. Others keep the lid secured with duct tape, bungee cords or even heavy items like weights or bricks.

One of the other problems with the tank setup is finding a way to set up your various filters and skimmers without giving the octopus access to them where they can either break them apart or find a hole to squeeze into. You have to be crafty as you design your octopus's system to make sure they can't sneak out.

Pet Octopus Behavior

The octopus is a highly intelligent animal that is thought to have the same level of intelligence and reasoning as a cat. They have been known to open shut jars with food inside and can figure out how to escape tanks.

They can also distinguish between different people. In fact, they are so intelligent that hobby keepers report that it's not unusual for an octopus to break out of their tank, slither over to one nearby and eat the fish and crustaceans, and then return to their own "home" tank.

One of the reasons octopuses have become popular with aquarium hobbyists is that this is one creature you can truly interact with. They can be trained and can learn to be hand fed. You should also spend time learning about octopus body language and "coloring," as they can change colors and their choice of hues actually indicates whether they are excited, stressed, or scared.

Providing Octopus Enrichment

The downside to the intelligence of the octopus is that this is an animal that can quickly become very bored. Providing them with toys, live food to hunt, and training can help alleviate this boredom. Any plastic, water-safe, non-metal item can be a toy, and some octopuses in captivity will play with small balls and toys made for cats and small animals. They also enjoy the following games.

  • Object play: Playing with shells and even your hands, although you should be careful to make sure they don't pull you too close to their beak and get bitten. They also enjoy playing with toy building blocks and straws.
  • Working for food: Making them work for their food also reduces boredom, such as putting some live ghost shrimp in a jar and closing the lid and giving it to them.
  • Maze and puzzle games: Due to their remarkable intelligence, octopuses enjoy problem-solving games. Set up an underwater maze with a tasty reward at the end, or present them with a puzzle box that contains a delicious morsel inside. They'll have to figure out how to navigate the maze or open the box to get their reward.
  • Rearranging their living space: Give your octopus safe materials to build and create with. They may enjoy rearranging their habitat, moving around stones, or stacking objects.
Octopus safe in its hide.

Pet Octopus Diet

Your octopus should be fed once a day. Most octopus species will prefer to have live food, though you can try to see if they will eat frozen. If you do feed frozen, make sure the food is thawed first. Even if they're willing to eat frozen, live is better as this provides them with mental and physical enrichment. They are carnivorous and can eat clams, crabs, crayfish, fish, scallops, shrimp, and squid.

Quick Tip

Do not feed them freshwater feeder fish, such as goldfish, as these can make them ill.

Tank Mates for an Octopus

Since the octopus is a carnivore and is aggressive, they cannot live in a tank with other aquatic creatures. They will actively hunt down and eat any fish or crustaceans that you add to a tank.

They also are shy creatures, so having tank mates would make them anxious and stressed. An octopus that is stressed can emit ink to defend itself, and this can be toxic to the octopus in such a small space. The only creatures you can safely put in the tank are a starfish or a non-spiked sea urchin.

Need to Know

Even placing two octopuses together will not work, as one will eventually kill and cannibalize the other.

Health and Lifespan of a Pet Octopus

Most species of octopus do not live very long in a tank, and generally have a short lifespan in the wild as well. You can expect a pet octopus to live about eight to 10 months, though some can live up to 2 years.

Octopus in a tank with liverock.

Cost of an Octopus

You will find a wide range of pricing for a pet octopus from specialty pet stores and online retailers. They can cost anywhere from $20 to $1,000. You will also need to figure in the cost of a tank, which can be several hundred dollars, especially since you need a tank with specific requirements to prevent escape. You also need to add in the cost of live food monthly, which is estimated around $100 a month, though this will depend on the size of your octopus.

Should You Keep an Octopus as a Pet?

It's no doubt that the octopus is an intriguing creature that can be more interesting and interactive than other typical aquarium residents. However, they do not live very long, they're expensive to keep, and you need to be absolutely sure your tank set-up is sound and escape proof.

Your octopus will also need constant care, so if you need to travel, you must be able to find a pet sitter experienced in caring for and feeding them. There's also a debate about whether it's humane to keep such an intelligent creature in a small space, and whether it's possible to provide them with enough mental enrichment to keep them from being bored and stressed. Keep these issues in mind when deciding to keep a pet octopus.

Guide to Keeping a Pet Octopus: Care, Legality, & Enrichment