Atlantic Lions Mane Jellyfish

Cyanea fulva

Originally described in 1862 by Louis Agassiz. Ernst Haeckel suggested C. fulva were just a synonym of C. capillata, whereas Alfred G. Mayer suggested they were a distinct variant of capillata. Ultimately, they were established as C. capillata until recently when the species Cyanea fulva was (rightfully) restored. Ranging from egg yolk yellow to burnt yellow with reddish brown tentacles and clear or purplish arms. Found from Virginia through New England in late winter and spring.

Cyanea fulva Juvenile atlantic lions mane jellyfish

Cyanea fulva ephyra atlantic lions mane jellyfish

Sometimes C. fulva ephyra are pink instead of orange!

Caring for Atlantic Lion's Mane Jellyfish

There is virtually no information on the care or life cycle of C. fulva because they were considered synonymous with C. capillata for so long. We hope to offer information unique to this species.

Stocking density: ALM jellies have hundreds of tentacles that stretch a considerable distance behind them. For this reason, they should be stocked at a minimal density. Larger, longer tanks are ideal so they have room to fully extend their tentacles. Exact stocking density will vary on the design, but ideally, these should be stocked at 1 jelly per 5 gallon aquarium, 2-3 per 10 gallon aquarium and 3-5 per 20 gallon aquarium.

Flow: With all those tentacles, these jellies can be sticky! They like to adhere to the sides of the tank or anything they can catch on. That being said, ALM jellies are fairly energetic and strong swimmers. Set the flow to medium and increase if they are getting stuck to the sides or bottom of the tank.

Feeding: ALM jellies eat just about anything they can get their tentacles on. In the wild, this may end up being fish larvae, plankton, and other species of jellyfish. In captivity, a varied diet of frozen mysis shrimp, baby brine shrimp, and jellyfish pellet foods are all good options. They will gladly eat other species of jellyfish, such as moon jellies, but this doesn't seem to be a requirement for this species. For jellies 1/2" diameter and under, feed live baby brine shrimp. Once they exceed 1/2", start incorporating diced mysis shrimp to their diet at least a few times per week.