Jellyfish are weird creatures, not because of their unusual shape but because of how well they survived for so long without a brain.

You heard it, correct? In fact, they are the oldest surviving creatures on Earth. These ocean-dwellers have lived for over 500 million years without a brain.

Only if humans did not have brains, we would have lived as long as jellyfish! Jokes aside, jellyfish do not have a brain, but they boast a unique nervous system with a net of nerves around their body that sends signals to their muscles, allowing them to swim, eat, and defecate, and they make excellent pets, too.

You must first know them well if you want to have them as an exotic pet. Let's find out ways not to kill them instead.

Do You Want a Pet Jellyfish?

Picture this: a softly glowing fish tank in your living room, filled with tiny translucent jellyfish gliding slowly, giving a sci-fi movie feel.

Raising jellyfish at home is like having your own mini-ocean; you should keep a pet jellyfish if you want to own it.

However, raising jellyfish is unlike keeping fish or turtles at home. You must provide a conducive environment for these oceanic creatures to thrive; ordinary fish tanks just do not cut it!

Seasoned jellyfish owners suggest you get a specially designed "Kreisel tank," a circular-shaped tank. Likewise, the water should be kept calm without bubbles, which can be fatal to jellyfish.

Ocean creatures like the Jellyfish need optimal salinity, pH, and temperature to survive, which is hard to maintain at home but not impossible.

On top of it, they only thrive on a diet of plankton and assorted meals, which can be slightly more pricey than a regular fish diet.

If you are up to take these challenges, go ahead and get a jellyfish, but it is better to avoid this idea if you cannot invest the required time and money in the first place.

To those aspiring jellyfish owners, continue reading further to learn more about ways to keep your pet alive and thriving.

How not to kill a Pet Jellyfish

Here is a guide for beginners to take good care of their first pet jellyfish.

1. Choose the Right Species for Beginners

For beginners, getting jellyfish that are easy to work with may be easy. Most seasoned pet owners will reply Moon Jelly (Aurelia aurita) because they are hardy, do well in small spaces, and do not sting. They may survive for one to two years.

Other popular yet easy jellyfish varieties include Lactoides and Cannonball jellyfish.

Lactoides may well live for over 18 months and do not sting, but they are tiny, just 4 cm long. Cannonball jellyfish are similar to Lactoides in terms of lifespan but are pretty big. They may get well over 8 inches in width and 5 inches in height.

Consult a pet jellyfish expert to find yourself a perfect first pet jellyfish.

2. Choose a Specialized Aquarium

Jellyfish do not survive long in a regular, rectangular fish tank. They might get stuck in the corners, get sucked into filters, or absorb bubbles that may appear from a sudden jerk of the tank.

Even tiny, invisible scratch can damage their soft skin. Therefore, experts suggest using a specialized tank called Kreisel, which is round, compact and creates zero bubbles.

The round shape of the tank creates a gentle, circular water flow that keeps the jellyfish suspended.

You can easily buy a Kreisel tank online or get an all-in-one kit to build one at home.

3. Source Oceanic Fish Diet

Tiny jellyfish have a strict diet of plankton, a small, floating creature found in seas and oceans, whereas giant jellyfish may feast on fish, shrimp, and crab.

However, finding plankton for pet jellyfish can be difficult. Consider buying baby brine shrimp from a specialized pet.

You can give a mix of food varieties such as live baby brine shrimp, dried planktonic food, krill, finely chopped seafood, and enriched rotifers. Most of these are easy to get by online if you know where to look.

Experts recommend feeding your baby jellyfish once or twice a day in smaller amounts. However, refrain from overfeeding them as it can desensitize them.

The amount of food fed will depend on the leftover after 90 minutes. If there is still food left, you should feed them less the next time.

4. Maintain Correct Water Salinity

Jellyfish are oceanic creatures requiring optimal water quality endemic to the ocean to thrive.

Here are a few factors you should know.

• Water type: Always use distilled water to fill jellyfish tanks, typically changing 10-20% of water weekly.
• Water pH and Salinity: Always check water for pH levels between 8.0-8.3 with salinity levels ranging from 32-35 ppt, and ammonia (NH3) and Nitrate (NO2-) at 0.0 levels.
• Temperature: The water temperature should be around 70°F at all times.
• Water flow: Create a consistent water flow with a circulation pump or powerhead, but keep it gentle to avoid disturbing their movement.

Remember that your jellyfish is under stress if it has shortened tentacles, weak pulsing, and size shrinking.

5. Opt for Dim, Low-Heat Lighting

Jellyfish thrive in dimly lit tanks, which suit their natural habitat where they roam in lowly light ocean depths.

Intense light can stress them, so you are advised to avoid brightly lighting the Kreisel tank.

LED lights work best for Kreisel tanks, creating a soft, even glow. Moreover, LEDs come in various colors, such as blue and purple tones, that mimic the ocean's natural light.

Dim lights also work great in enhancing your jellyfish's translucent appearance. Many seasoned pet owners advise keeping the LED light on for 12 hours with 12 hours of darkness, helping keep Algae growth to a minimum.

You can also use a clock timer to switch on or off the Kreisel tank.

6. Regularly Clean the Kreisel Tank

Jellyfish tanks need regular cleaning, too, especially from algae, jellyfish poops, uneaten food, and poor water quality.

• Cleaning Kreisel tanks regularly helps check water chemicals at their level, especially if there is any ammonia and nitrates.
• Jellyfish poop and uneaten food will sink to the tank floor, rot, and may contaminate the water.
• Uncleaned jellyfish tank water will grow and accumulate algae over time, clouding the walls and bottom.

How Often Should You Clean the Tank?

• Remove any uneaten food after each feeding by skimming debris or water floating in the water.
• Partially change the water (10-20%) every week and regularly clean filters or pumps.
• Always use a non-abrasive sponge or scraper to remove algae from inside the tank walls and bottom.

7. Monitor Health and Stress Signals

Monitoring pet jellyfish's health and stress signs is essential because they will only show subtle changes in their appearance and behavior.

Here are a few tell-tale physical signs to look out for.

• An erratic or weak movement
• Weak or arrhythmic pulsating
• Shriveling or shrinking bell
• Cloudy or "milky" appearance
• Torn or uneven tentacles and tears in the bell
• Floating past the food without attempting to feed
• Incomplete digestion
• Constantly sinking or staying at the bottom
• Floating upside-down or sideways
• Yellowing, browning, or unusual discoloration

How to Revive Your Jellyfish?

• Start by checking the water quality and adjusting the parameters immediately.
• Ensure the water flow is gentle and consistent.
• Avoid overfeeding and rest the feeding time to small dosages twice or thrice a day.
• If their condition does not improve, consult an aquatic veterinarian immediately.

Fun Facts about Jellyfish

• Jellyfish predate dinosaurs by hundreds of millions of years, at least two or three times older than the first known dinosaur 'Megalosaurus' that showed up 243 million years ago.
• Jellyfish are not the only creatures without a centralized brain; coral, fungi, sea stars, sea urchins and anemones, bacteria, and even slime molds boast no brain but a net of sensory nerves around their bodies.
• Jellyfish are the only time travelers on Earth, but not literally! Turritopsis nutricula species of jellyfish can turn back from an adult to a Polyp (a beginning stage of life) during stress, making them immortal.
• This may sound like straight out of a science fiction! Jellyfish can clone itself by regenerating and creating two new organisms when cut in half, using summarization and transdifferentation.
• Many jellyfish species can glow in the dark to help navigate the surroundings and distract predators. It occurs due to a chemical reaction where luciferin substance reacts with oxygen and releases light-turning energy.
• Did you know jellyfish are 95% water? The only other creature that is mostly water is earthworm, which is 90% water.
• Although negligible in numbers, Jellyfish maintain the ocean ecosystem by eating fish eggs and larvae, which frees up resources for less established fish species, helping them grow and thrive.
• Jellyfish can range from a few centimeters to a hundred feet or more. Lion’s mane (Cyanea capillata) is the largest jellyfish species, reaching 120 feet (36.5 meters).
• All jellyfish have tentacles, but not all of them are poisonous. For example, moon jellyfish have a mild sting, while Irukandji jellyfish can send fire stingers that may cause fatal brain hemorrhages.
• Some jellyfish trap their prey by arranging their tentacles in a twisted, spiral pattern, while others drag their tentacles behind like a trawler net as they drift.

Conclusion

Jellyfish are excellent pets for an avid aquarist, but beware of making mistakes while raising the delicate oceanic creature.

Acquiring a common pet jellyfish like a moon jellyfish may cost anywhere from $25 to $50. A Kreisel tank may cost another $200-$300, with jellyfish foods costing from $30 for dry food to $130 for Brine shrimp eggs (50g).

Consult an expert to learn more about the challenges of raising a pet jellyfish. Get in touch with Urban Pet Hospital to consult an experienced Veterinarian in Urbandale.