Leidyi's Comb Jelly
Mnemiopsis Leidyi
Leidy's Comb jellies are truly remarkable creatures. Just 13 days after birth, Mnemiopsis is capable of reproducing. As simultaneous hermaphrodites, this also means they can self-fertilize. Consuming ten times its body weight in food, accidental introduction of Mnemiopsis have been devastating to local ecosystems. Rather than moving by pulsating, comb jellies glide through the water by moving hundreds of flat combs found in eight rows on their bodies. These glassy combs catch light and refract it into a rainbow light show that is sure to draw the attention of anyone.
Caring for Comb Jellies
Comb jellies are possibly the most challenging species available to the home aquarist. When things go wrong, Comb jellies tend to quickly deteriorate, leaving little or no time to fix a mistake. However, Ctenophores have remarkable abilities to regenerate nearly all of their body, and at unparalleled speed. With a few special requirements and care, you'll be able to successfully keep Comb Jellies in no time. So what does it take to keep this species?
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Leidyi's Comb Jellies can be found in an incredibly wide range of temperatures and salinities. Let's use this to our advantage. Comb Jellies won't tolerate even moderate amounts of ammonia so ensure your tank is completely cycled and matured before adding them. Additionally, they are fairly susceptible to bacterial infections. By keeping their tank on the cooler side, bacterial blooms will be less likely and your jellies metabolism will slow down as well. This means less feeding required, longer life spans and a cleaner tank. We also highly recommend adding a UV sterilizer to their holding system.
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Stocking density: Without any true tentacles to tangle, you can stock your tank pretty densely. Be cautious of bioload- too many jellies added at once can crash your cycle and lead to ammonia, bacterial bloom or both.
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Flow: Low flow is a must with these jellies. Just enough to keep them cruising around their tank.
Feeding: Comb Jellies will accept live baby brine shrimp and rotifers. They will gladly consume live fish fry or eggs if you can source these. ​
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Temperature Range: 60-72 F ( ideally 60-68 F)
Salinity: 1.023 SG or 31 ppt
Life Stages
Comb Jellyfish aren't true jellyfish and actually belong to an entirely different phylum called Ctenophora. As such, their life cycle differs quite a bit from that of true jellyfish (Scyphozoa).