What do Healthy Jellyfish Look Like?

Jellyfish are strange and very foreign creatures. They’re often compared to alien spacecraft, and deservingly so. Unfortunately, these enigmatic creatures don’t have brains or mouths to tell us when they’re upset. As jellyfish guardians, we have to be able to tell the difference between a healthy jellyfish and a sick one.

For this post, we’re going to be using the Moon Jellyfish for all of our examples. Other species may vary slightly, but should be very similar.

What does a healthy jellyfish look like?

A healthy jellyfish should have an even, round bell. Their bodies should be fairly thick, and smooth. A happy moon Jellyfish will have hundreds of tiny fringe tentacles at the edge of the bell, and four mouth arms in the center. It should pulse once every few seconds.

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In the above photo, notice how there are tons of long, hair like tentacles at the edge of the bell. These “fringe tentacles” are a good indicator of health. They should be long, relaxed and flow smoothly as the jellyfish pulses. They do tend to retract these while eating, so don’t be alarmed if they temporarily disappear!

Also notice the width of the bell. This is exactly how wide a healthy Moon Jelly should be. Thinner ones are less nourished, and may not be getting enough nutrition. IMG_1013.jpg

Note that the bells are round and very smooth. The jellies maintain a sort of half circle form. They aren’t thin like plates, but also aren’t balled up into a sphere. Both extremes are bad signs.

We hope this post can be used as a reference guide for your own jellies at home. Stay tuned, as our next post will be on common jellyfish ills and ails.

At the Jellyfish warehouse, we put the highest level of effort and research to create happy and healthy jellyfish for the home aquarium. You can purchase your own here: Jellyfish Warehouse

How to Care For Your Pet Mangrove Box Jellyfish

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An adult Mangrove Box Jellyfish.

A popular jellyfish we offer are Mangrove Box Jellyfish. These odd little jellies are both entertaining and mysterious. They originally come from the Caribbean and surrounding areas.

Mangrove Box Jellyfish only get about 1″ in bell length and 2-3″ total length. This makes them perfect for small home jellyfish aquariums. They rapidly dart around the aquarium, making them instantly captivating.

What do they eat? In the wild, Mangrove Box Jellyfish eat live copepods, or plankton. When we first collected these jellies, this was an issue. They didn’t like to eat anything but wild plankton. We were able to selectively breed these jellyfish to produce a line that readily accept live Baby Brine shrimp. This may be easy enough for some and too much of a hassle for others.

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A day old Mangrove Box Jellyfish. They later grow three tentacles on each corner.

What parameters should the water be? Mangrove Box Jellyfish should be kept at a salinity of 1.020 – 1.024 (27-32ppm) and a temperature of 77-80 F. These jellies prefer fairly strong flow, but seem to enjoy a variety of aquariums. We recommend they be kept in a Cnidarium Nano or an Orbit 20. Fairly tolerant of less than perfect water quality and conditions, these make a good beginner jellyfish. They should be housed with other Mangrove Box Jellyfish only.

Do they sting? Box Jelly immediately makes people think of the lethal Australian Box Jellies. Luckily, Mangrove Box Jellyfish are an entirely different story. They have a small, non lethal sting. Some report no feeling at all, whereas others report minor irritation or stings. As usual, we recommend you exercise caution when handling these jellies. If you know you have sensitive skin, you may be more prone to jellyfish stings.

 

You can buy your own pet Mangrove Box Jellyfish and jellyfish aquarium at our online store: Jellyfish Warehouse

IMG_9697Check out our video on Mangrove Box Jellyfish!