Guide To Keeping Healthy Pet Seahorses

Angelina Childree, LVT
By Angelina Childree, LVT. Reviewed by Sean Perry, DVM on Feb. 21, 2024
Yellow seahorse

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In This Article

Pet Seahorse Tank

Seahorses have lived in our oceans for millions of years and are one of the easiest fish to recognize. You may have seen seahorses while visiting an aquarium or zoo, but they’re becoming increasingly popular pets for advanced fish enthusiasts, too.

Here’s what to know before purchasing a pet seahorse.

Pet Seahorse Tank

Tank setup and maintenance are the most essential parts of keeping healthy pet seahorses. Water quality, filtration, tank size, and lighting play vital roles in a seahorse's health.

These are important things to consider when setting up your seahorse tank:

Tank Size

30 gallons, plus 10 gallons for each pair of seahorses added


4 times/hour


28–32 parts per thousand (ppt) (or a specific gravity between 1.021–1.025)


 (may be species dependent)

75–80 F





Avoid bright lights; can have dim sections


Cleaning and Maintenance

Part of effectively maintaining an aquarium with healthy seahorses is monitoring. The temperature should be checked daily, while water quality can be checked weekly. If your aquarium's water parameters are not within normal range, monitor water quality more frequently until they have stabilized.

Top off water levels as needed to maintain constant salinity. Perform partial water changes of 25% or less of the total amount in your aquarium every two to four weeks, or based on water quality parameters. Avoid water changes of larger volumes to keep healthy bacteria in your pet seahorse's environment. Avoid waiting until your water parameters are abnormal to perform water changes; this makes returning to healthy parameters more challenging.

Tank Decor

Seahorses use their prehensile tails to grasp onto items in their environment, using them almost like an anchor. Because seahorses aren’t strong swimmers, it’s essential that their tank contains plants and decor they can grasp horizontally with their tail.

Artificial and live plants are common items for seahorses to grasp onto, but other decor, such as ropes, can also be used. Do not use any décor with metal or sharp points that could potentially hurt your seahorse.

Some live corals may be OK in your pet seahorse's tank, but they can potentially harm your seahorses—and vice versa. Many corals can sting seahorses and seahorses can break corals with their tails, so both species can be at risk for health problems by living together.

Pet Seahorse Tankmates

Seahorses are rather social fish, so keeping at least a pair together is best. When selecting a pair of pet seahorses, make sure they are the same gender to avoid seahorse babies (they can have up to 1,000 in one brood!). Juvenile pet seahorses may not be old enough to be identified as male or female when purchasing. Only purchase pet seahorses from a supplier who can identify the gender appropriately.

Even though seahorses are social creatures, they can only share a tank with a few other aquatic species. Peaceful fish like gobies or invertebrates like snails can be housed with pet seahorses, but monitoring is crucial—because seahorses are not strong swimmers, they cannot compete with most fish for food, If your seahorse is not eating or if another fish is showing aggression toward your pet seahorse, remove them from the tank.

When adding fish to your seahorse tank, slowly add them in small numbers. Ideally, all fish should be kept for the first two to four weeks in a quarantine tank to avoid potentially infecting your established tank with any diseases.

Pet Seahorse Food

Seahorses are carnivores and eat a variety of crustaceans. Mysis shrimp should be a staple in your pet seahorse's diet—not frozen shrimp. Allow frozen foods to thaw before feeding them to your seahorse. Avoid microwaving food and refreezing food items, as that may allow bacteria to form and alter the nutrients.

Because seahorses digest food quickly, feeding them small, frequent meals is ideal.

Other crustaceans, like brine shrimp, are OK as treats but have little nutritional value. Baby brine shrimp can contain more nutrients due to having a yolk reserve and can be used as a live prey treat.

Because seahorses digest food quickly, feeding them small, frequent meals is ideal. Pet seahorses should be fed two or three times a day, and they can be fed a few different ways:

  • Free feeding: Pour the food into the tank, and remove any leftover food later. This method can be an easy way to feed your pet seahorses, but food may be left behind and potentially spoil. If you have a large seahorse colony, free feeding can make feeding time easier.

  • Feeding station: Designated feeding stations can help better maintain tank cleanliness. Typically, your pet seahorse will learn to eat at a feeding station within a few weeks. You can use a turkey baster to add the food to the bowl on your feeding station.

  • Hand feeding: Similar to the feeding station, hand feeding can take some time as your seahorses get used to coming closer to you. This is a fun way to feed your seahorses and can sometimes allow you to see potential health problems better. Hand feeding can also be helpful to transition a pet seahorse from live food to thawed food, as it enables you to move the food item, giving it a more natural and lifelike appearance. This option is typically better for smaller seahorse colonies.

Pet Seahorse Health

Seahorses are at risk for some common diseases seen in other types of fish. These conditions include:

  • Bacterial and fungal infections

    • Mycobacterium syngnathidarum

  • External and internal parasites

  • Dropsy

  • Swim bladder disorders

  • Gas bubble disease

  • Bodily trauma

Pet seahorses can get diseases from you and vice versa. Always wear gloves when handling food or items that have come in contact with your aquarium's water for the safety of both you and your aquarium.

Many health problems in pet seahorses, like those in other animals, can be prevented by properly caring for their environment. However, even with the best husbandry, seahorses can still become sick, so monitoring them for potential health changes is essential.

Even though you may not need a veterinarian if you have a healthful tank, finding a local aquatic vet is crucial so you are prepared if your seahorse becomes sick. If you notice any of the following symptoms in your seahorse, contact your vet immediately:

  • Abnormal swimming patterns or floating to the surface

  • Rapid breathing

  • Decreased appetite

  • New growths, lumps, or lesions

  • Difficulties grasping with their tail

  • Cloudiness of the eye

  • Flared gills

  • Color changes

  • Itching/rubbing against decor and other items


1. Garcia D, Garrick-Maidment N. Seahorse Manual. The Seahorse Trust, England. 2010.

2. Burhans R, Melechinsky D. Seahorse Husbandry and Propagation. Birch Aquarium, Scripps Institution of Oceanography, University of California San Diego.

3. Most threatened species. IUCN SSC Seahorse, Pipefish & Seadragon Specialist Group.

4. Qin G, Zhang Y, Huang L, Lin Q. Effects of water current on swimming performance, ventilation frequency, and feeding behavior of young seahorses (Hippocampus erectus). Journal of Experimental Marine Biology and Ecology. 2014;461:337-343.

5. Giwojna P. Nutrition Part III: Hand Feeding Adult Seahorses. 1996.


Angelina Childree, LVT


Angelina Childree, LVT

Veterinarian Technician

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