Japanese Sea Nettle
Chrysaora pacifica
A striking open-water predator that demands a very specialized setup.
About
The Japanese sea nettle (Chrysaora pacifica) is one of the more accessible jellyfish species available to dedicated invertebrate keepers, native to the open coastal waters off Japan and Korea in the western Pacific. Its bell ranges from a modest couple of inches up to nearly a foot across, fringed with long, trailing tentacles that drift with an almost hypnotic quality in the water column. Those tentacles are functional hunting tools. This is an active predator that captures zooplankton and small organisms with stinging cells, so the peaceful temperament label applies only to how it interacts with other jellies of similar size, not to anything small enough to eat. Housing requirements are genuinely non-negotiable here: a kreisel tank, the circular or cylindrical vessel designed to keep jellyfish suspended in a gentle rotating current, is the only appropriate setup. A standard rectangular aquarium will damage or kill them against intake pipes and corners. Fish and most invertebrates cannot share the same water. Feeding requires appropriately sized live or frozen zooplankton, and water quality must stay consistently high. With a natural lifespan of roughly one year, this is a short-term commitment that rewards patient, detail-oriented keepers who enjoy one of the ocean's most ancient and otherworldly animals.
Good tank mates
Species that tend to coexist peacefully with Japanese Sea Nettle
Frequently asked questions
- How big does the Japanese Sea Nettle get?
- The Japanese Sea Nettle reaches about 2–12" as an adult.
- What size tank does the Japanese Sea Nettle need?
- A minimum of 30 gallons is recommended for the Japanese Sea Nettle.
- What water parameters does the Japanese Sea Nettle need?
- The Japanese Sea Nettle does best with a temperature of 50–72°F, a pH of 8–8.3.
- Is the Japanese Sea Nettle aggressive?
- The Japanese Sea Nettle is generally peaceful and suits a community tank with similarly calm tankmates.
- What does the Japanese Sea Nettle eat?
- The Japanese Sea Nettle is a carnivore. It needs a meaty, protein-rich diet of frozen or live foods.
- How long does the Japanese Sea Nettle live?
- With good care, the Japanese Sea Nettle typically lives 1 year.