Octopuses, with their mesmerizing intelligence, complex behaviors, and otherworldly appearance, have captivated humans for centuries. Their ability to solve puzzles, change color, and even escape seemingly impossible enclosures sparks a unique fascination. This allure naturally leads to the question for many aquarium enthusiasts: Can You Keep An Octopus As A Pet? The answer is yes, it is possible, but it comes with significant considerations that go far beyond the typical fish or even invertebrate pet. This guide will delve into the realities of octopus ownership, exploring their specific needs and whether welcoming one of these incredible creatures into your home is the right decision for you.
Understanding the Octopus: An Extraordinary Invertebrate
Before considering octopus ownership, it’s crucial to appreciate their unique biology. Octopuses belong to the phylum Mollusca, placing them in the same broad group as snails and clams, but they are specifically classified within the class Cephalopoda, alongside squids, cuttlefish, and nautiluses. This group, meaning “head-foot,” is characterized by their prominent heads and feet modified into tentacles. For a deeper dive into mollusk biology, resources like the Introduction to the Molluscs article and the Tree of Life web pages offer extensive information. The Cephalopod web page and the National Resource Center for Cephalopods are also invaluable resources for those seeking comprehensive knowledge about these fascinating animals.
One of the defining characteristics of octopuses is their remarkable intelligence. They exhibit problem-solving skills, complex communication, and even demonstrate personality. However, it’s important to understand that their “entire natural lifespan” is relatively short, typically ranging from 1 to 2 years for most tropical species. This brevity is a significant factor to consider when thinking about keeping an octopus as a pet.
It’s also vital to dispel a common misconception: reef tanks are generally unsuitable environments for octopuses. While octopuses require pristine water conditions similar to a reef aquarium and appreciate ample hiding places and good water flow, a typical reef setup presents several challenges. Most octopuses are nocturnal or prefer subdued lighting, contrasting sharply with the intense illumination favored in reef tanks. Furthermore, their predatory nature and specific environmental needs make them incompatible tank mates for most reef inhabitants.
An octopus utilizes its camouflage in a home aquarium, emphasizing the need for appropriate hiding places and a suitable environment for these intelligent creatures.
Is Octopus Ownership Right for You? Key Considerations
Deciding to keep an octopus as a pet is a significant commitment that demands careful consideration of several factors:
Commitment and Lifespan: While their lifespan is short, the care they require is intensive and constant. You must be prepared for a relatively brief but engaging pet ownership experience.
Tank Environment: An octopus needs a species-specific tank, not a reef tank. Their requirements differ substantially from typical reef inhabitants.
Nocturnal Nature: Most octopus species are nocturnal. If you desire a pet that is active during daylight hours, an octopus might not be the best choice. Even diurnal species prefer less intense lighting than a reef tank typically provides.
Escape Artists: Octopuses are notorious escape artists. They can squeeze through incredibly small openings and even open lids. Tank security is paramount. As a rule of thumb, if you can fit your pinky finger into a gap, an octopus can likely escape through it. Pygmy octopuses can escape through even smaller spaces. Secure, tightly fitting lids are non-negotiable. There are even documented cases of octopuses escaping tanks to raid neighboring aquariums for food before returning home!
Specialized Diet: Octopuses are predators with specific dietary needs. They require a diet rich in mollusks and crustaceans, not just any fish food.
Ethical Sourcing: Consider the ethical implications of sourcing an octopus. Ideally, opt for captive-bred specimens when available to reduce the impact on wild populations. However, captive breeding is still not widespread for many octopus species.
Creating the Ideal Octopus Habitat: Tank Setup Essentials
If you’re prepared for the challenges and still enthusiastic about keeping an octopus, setting up the right tank is the first crucial step:
Tank Size and Security: The tank size depends on the octopus species, but generally, larger is better. A minimum of 30 gallons is recommended for a smaller octopus, but larger species will need significantly more space. The tank must be absolutely escape-proof. A well-sealed top, potentially secured with bungee cords or weights, is essential. Some aquarists even use duct tape for added security.
Avoiding Open Tops: Open-top tanks, common in reef setups for gas exchange and lighting, are not an option for octopuses due to their escape abilities.
Creative Escape-Proofing Strategies:
- Deep Tanks with Low Water Levels: Some public aquariums utilize very deep tanks filled only partially, creating a significant climbing distance. This is less practical for home aquariums.
- Astro-Turf Barriers: Lining the upper rim of the tank with Astro-Turf can deter some octopuses, but it’s not foolproof and can be aesthetically unappealing.
- Sealed Tank with Sump: The most recommended method is a well-sealed tank that overflows into an open sump. The sump, placed below the main tank, houses filtration equipment and allows for gas exchange without compromising tank security.
Substrate and Decor: Provide a substrate of sand or fine gravel. Crucially, offer numerous hiding places. Octopuses are natural den dwellers and need secure retreats to feel comfortable. Rocks, caves, PVC pipes, and even sturdy ceramic decorations can serve as excellent dens.
Lighting: Subdued lighting is preferable. Avoid intense reef-style lighting. Red or blue lights can be used for nighttime viewing as octopuses are less sensitive to these wavelengths.
Water Flow: Octopuses prefer moderate to high water flow. However, powerheads, commonly used for flow in aquariums, pose a significant risk. Octopuses are incredibly tactile and will explore powerhead intakes, risking injury to their sensitive arms from the impeller.
Safe Flow Solutions:
- Overflow and Sump with Remote Pump: The safest approach is to use an overflow system leading to a sump with a remote pump to circulate water. This eliminates powerheads from the main tank.
- Carefully Shielded Powerheads (with extreme caution): If powerheads are unavoidable, they must be meticulously shielded. However, octopuses are adept at removing shields. Friction-fit baskets are easily dislodged, even when glued. Powerheads are generally discouraged in octopus tanks.
Overflow Protection: Even overflows need to be octopus-proofed. Cover the overflow with mesh fine enough to prevent escape but large enough to avoid clogging with shed skin and debris. PVC standpipes with glued-in bioballs or secured plastic mesh are common solutions. Regular cleaning of the overflow is essential to prevent clogs and tank overflows.
An octopus sucker pad detail emphasizing the tactile sensitivity of their arms and the potential danger of unprotected powerheads.
Maintaining Pristine Water Quality: Filtration is Key
Octopuses, despite some research showing tolerance to less-than-perfect water parameters, thrive best in high-quality water, particularly regarding oxygen levels and the absence of heavy metals.
Filtration Requirements:
- Mechanical Filtration: Essential for removing shed skin, uneaten food, and other particulate matter. Power filters are effective for mechanical filtration, but require frequent cleaning (possibly multiple times a week) due to the high bioload and shedding. Clogged filters can be detrimental.
- Biological Filtration: A robust biological filter is necessary to process waste. A sump system greatly enhances biological filtration capacity.
- Chemical Filtration: Activated carbon is highly recommended. It helps remove organic pollutants and is particularly crucial for mitigating the effects of inking.
Protein Skimmers: Non-Negotiable: Protein skimmers are considered essential for octopus tanks. They offer two vital benefits:
- Enhanced Gas Exchange and Oxygenation: Skimmers significantly increase oxygen levels in the water, critical for octopuses due to their high oxygen demand.
- Waste Removal: Skimmers efficiently remove organic waste before it breaks down, improving overall water quality.
Water exiting a protein skimmer typically has a dissolved oxygen concentration close to saturation (~6 mg/L in a typical marine aquarium). Maintaining high oxygen levels and efficient gas exchange is paramount for octopus health. Low oxygen levels are a common and often overlooked problem in home aquariums, particularly sealed tanks.
Water Parameters:
While octopuses are more tolerant than initially believed, maintaining good water parameters is still important:
- Temperature and Salinity: Keep within typical marine aquarium ranges (refer to Table 1 from the original article for specific saturation values based on temperature and salinity).
- pH: Maintain a stable pH, ideally around 8.0-8.3. While studies show tolerance down to 7.5, optimal conditions are preferable.
- Ammonia and Nitrite: Keep at 0 ppm through effective biological filtration.
- Nitrate: Keep as low as possible, ideally below 20 ppm. While octopuses can tolerate higher levels, reproduction may be affected above 100 ppm.
- Heavy Metals (especially Copper): Absolutely avoid copper and other heavy metals. They are highly toxic to invertebrates, including octopuses. Ensure all aquarium equipment and medications are copper-free.
Table 1: Oxygen saturation concentration (mg / L) as a function of salinity and temperature of aquarium water.
| Temperature (°C) | 0 ppt | 10 ppt | 20 ppt | 30 ppt | 40 ppt |
|---|---|---|---|---|---|
| 10 (~50°F) | 13.0 | 12.2 | 11.4 | 10.6 | 9.8 |
| 15 (~59°F) | 10.3 | 9.7 | 9.2 | 8.6 | 8.1 |
| 20 (~68°F) | 9.4 | 8.8 | 8.4 | 7.9 | 7.4 |
| 25 (~77°F) | 8.5 | 8.0 | 7.6 | 7.2 | 6.7 |
| 30 (~86°F) | 7.8 | 7.4 | 7.0 | 6.6 | 6.2 |
Oxygen Saturation and Exchange: Maintaining high oxygen levels is not just about saturation concentration but crucially about the exchange rate of oxygen. Ensure sufficient water movement and surface agitation to facilitate efficient gas exchange. Protein skimmers are key for this.
Feeding Your Octopus: A Predator’s Feast
Proper nutrition is vital for octopus health and longevity. Avoid common pitfalls and provide a diet that mimics their natural prey:
Natural Diet: Octopuses are carnivores, primarily feeding on mollusks and crustaceans in the wild.
Appropriate Food Sources:
- Crustaceans: Shrimp (live or frozen, thawed), crabs, crayfish, ghost shrimp are excellent choices. Live crustaceans offer enrichment through hunting.
- Mollusks: Clams, mussels, and snails (though snails may be less practical as feeders).
- Fresh Seafood: Offer a variety of fresh seafood from seafood markets or Asian grocery stores to ensure nutritional diversity.
Avoid Feeder Goldfish: Feeder goldfish are extremely detrimental to octopus health. They are excessively high in saturated fat, leading to liver problems and significantly shortened lifespans. Goldfish are nutritionally inappropriate and should never be fed to octopuses.
Live vs. Frozen Food:
- Live Food: Offers enrichment by stimulating hunting behavior. Ghost shrimp and crayfish are readily available live options. Consider gut-loading live feeders with nutritious fish food before feeding them to your octopus.
- Frozen Food: Good quality frozen shrimp and other seafood are acceptable alternatives, especially when live food is unavailable. Always thaw frozen food completely before feeding.
Feeding Frequency and Amount: Feed octopuses several times a week, offering portions roughly the size of their mantle (body). Observe your octopus’s appetite and adjust feeding accordingly. Remove uneaten food promptly to maintain water quality.
Direct hand-feeding of an octopus with shrimp using tongs, demonstrating a method for providing food and interacting with your pet.
Enriching Your Octopus’s Life: Stimulation is Essential
Octopuses are highly intelligent and require mental stimulation to thrive in captivity. Environmental enrichment is not optional; it’s crucial for their well-being and can prevent stress behaviors.
Importance of Enrichment: Lack of stimulation can lead to:
- Stress Behaviors: White color patterns, inking, deimatic displays (startle flashing), autophagy (arm-eating), excessive hiding, erratic jetting, and escape attempts (“suicides”).
- Boredom and Depression: A monotonous environment can negatively impact their mental and physical health.
Enrichment Strategies:
- Varied Hiding Places: Provide multiple dens of different sizes and materials (rocks, caves, shells, containers). Rearrange dens periodically to create novelty.
- Toys and Puzzles: Introduce aquarium-safe toys like ping pong balls, cat toys (ensure no small parts), and puzzle feeders. Rotate toys regularly to maintain interest.
- Food Enrichment:
- Live Prey: Hunting live prey is a natural enrichment activity.
- Puzzle Feeders: Place food inside containers with lids or drilled corks that the octopus must figure out how to open. Bamboo skewers with shrimp or other food items can also provide a challenge.
- Varied Feeding Methods: Use tongs, skewers, or hide food in different locations in the tank to keep feeding engaging.
Interaction and Observation: Spend time observing your octopus and interacting with it gently. Many octopuses learn to recognize their keepers and may become more interactive over time. Positive interactions and a stimulating environment can significantly enhance their quality of life and make them more engaging pets.
Choosing an Octopus Species: Size and Temperament Matter
While the article doesn’t explicitly recommend specific species, when considering keeping an octopus as a pet, species selection is important.
- Pygmy Octopuses (e.g., Octopus mercatoris, Octopus joubini): Smaller species are generally more manageable for home aquariums due to their size and tank space requirements.
- Larger Octopuses (e.g., Octopus vulgaris): Require significantly larger tanks and are more demanding in terms of care.
- Blue-Ringed Octopuses (Hapalochlaena spp.): Never consider blue-ringed octopuses as pets. They are among the most venomous marine animals and pose a serious threat to human life.
Legality and Ethical Sourcing: Research the legality of keeping octopuses in your area. Prioritize ethically sourced octopuses, ideally captive-bred if available. However, wild-caught octopuses are still more common in the pet trade. Inquire about the octopus’s origin and ensure it was collected sustainably and humanely.
The Realities of Octopus Pet Ownership: Be Prepared for Challenges
Despite their captivating nature, keeping an octopus as a pet presents several challenges:
- Short Lifespan: Be emotionally prepared for a relatively short pet ownership experience, typically 1-2 years.
- Demanding Care: Octopuses require specialized care, time, and attention. This is not a low-maintenance pet.
- Escape Risk: Constant vigilance is required to prevent escapes.
- Messy Eaters and High Bioload: Octopuses produce a significant amount of waste, requiring robust filtration and frequent maintenance.
- Veterinary Care: Finding a veterinarian experienced with cephalopods can be challenging.
- Cost: Setting up and maintaining an octopus tank can be expensive, including specialized equipment, food, and ongoing maintenance.
Conclusion: Is an Octopus the Right Pet for You?
Keeping an octopus as a pet is an extraordinary undertaking. While it’s possible to provide a suitable captive environment and witness their incredible intelligence and behaviors firsthand, it demands a significant commitment of time, resources, and responsibility.
Octopuses are not suitable pets for everyone. They are best suited for experienced aquarists who are prepared to dedicate themselves to providing the specialized care these fascinating creatures require. If you are fascinated by octopuses and willing to meet their complex needs, the experience can be incredibly rewarding. However, it’s essential to enter into octopus ownership with realistic expectations and a deep understanding of the commitment involved. Consider whether you can truly provide the environment and care necessary for an octopus to thrive before bringing one of these remarkable animals into your home.
References
- Adey WH, Loveland K (1998) Dynamic Aquaria: Building Living Ecosystems. Academic Press, San Diego, CA
- Bailey TG, Youngbluth MJ, Owen GP (1994) Chemical composition and oxygen consumption rates of the ctenophore Bolinopsis infundibulum from the Gulf of Maine. Journal of Plankton Research 16: 673-689
- Boyle PR (1987) Cephalopod Life Cycles. Academic Press, London, UK, 441 pp.
- DeRusha RH, Forsythe JW, DiMarco FT, Hanlon RT (1989) Alternative diets for maintaining and rearing cephalopods in captivity. Laboratory Animal Science.
- Hanlon RT, Forsythe JW (1985) Advances in the laboratory culture of octopuses for biomedical research. Laboratory Animal Science.
- Haywood M, Wells S (1989) The Manual of Marine Invertebrates. Tetra Press, Morris Plains, NJ.
- Johnston L, Forsythe J (1993) An Octopus in Your House? – Part II. Aquarium Fish Magazine 5
- Kraines S, Suzuki Y, Yamada K, Komiyama H (1996) Separating biological and physical changes in dissolved oxygen concentration in a coral reef. Limnology and Oceanography 41: 1790-1799
- Kuhl M, Cohen Y, Dalsgaard T, Jorgensen BB, Revsbech NP (1995) Microenvironment and photosynthesis of zooxanthellae in scleractinian corals studied with microsensors for O2, pH and light. Marine Ecology Progress Series 117: 159-172
- Leclercq N, Gattuso JP, Jaubert J (1999) Measurement of oxygen metabolism in open-top aquatic mesocosms: application to a coral reef community. Marine Ecology-Progress Series 177: 299-304
- Nesis KN (1982) Cephalopods of the world. T.F.H. Publications, neptune City, NJ
- Ng WJ, Kho K, Ho LM, Ong SL, Sim TS, Tay SH, Goh CC, Cheong L (1992) Water- quality within a recirculating system for tropical ornamental fish culture. Aquaculture 103: 123-134
- Toonen R (1998) Reefkeeper’s Guide to Invertebrate Zoology, Part 13: Introduction to the Molluscs
- Toonen R (2000) Invert Insights: Dissolved oxygen in the reef aquarium. Tropical Fish Hobbyist #531: 86-90
- Toonen R (2001) Invert Insights: Why feeder goldfish make lousy food for marine predators. Tropical Fish Hobbyist #547: 94-99
- Wood JB (1994) Don’t fear the raptor: an octopus in the home aquarium. Freshwater and Marine Aquarium (FAMA) 17: 128-144
- Wood JB, Wood DA (1999) Enrichment for an advanced invertebrate. The Shape of Enrichment 8: 1-5
