Pulsating pink jelly-like creature

[onlyreefers]

I have some sort of new creature on my glass. It is small, circular and pink. It constantly pulsates, in a contracting, circular motion. Glanced over the hitchikers guide and did not see anything similar.

 

[onlyreefers]

Different picture…

 

[EeyoreIsMySpiritAnimal]

Medusa form of a hydroid, probably. How old is your tank?

 

[onlyreefers]

Medusa form of a hydroid, probably. How old is your tank?

This setup is 6 weeks old.

 

[EeyoreIsMySpiritAnimal]

This setup is 6 weeks old.

These are very common in new tanks and will go away on their own soon

 

[onlyreefers]

These are very common in new tanks and will go away on their own soon

Thanks! Just never seen or heard of anything like it

 

[EeyoreIsMySpiritAnimal]

Thanks! Just never seen or heard of anything like it

You're going to find all kinds of cool stuff

 

[onlyreefers]

This thing has grown, it’s awesome, but still can’t identify, just pulses 24/7. Hard to get a good pic.

 

[onlyreefers]

 

[Alexraptor]

I'ts really hard to tell from those pictures, but is it laying loose on the sand, pulsing with frilly bits/tentacles pointed towards the sky?

Because I almost think it looks like an upside down jellyfish, Cassiopeia sp.

 

[onlyreefers]

I'ts really hard to tell from those pictures, but is it laying loose on the sand, pulsing with frilly bits/tentacles pointed towards the sky?

Because I almost think it looks like an upside down jellyfish, Cassiopeia sp.

I don’t know about how loose. Thought about poking near it to see if it moved. Started on the glass and has been resting in the sand since. It’s typically stationary. I never spot it moving.

I did take a google search of the upside down jellyfish, and it looks like that’s exactly what it is!! Thanks!

Do they sting corals, people, fish? Seeing that they are typically sand resters on the search.

 

[Alexraptor]

I don’t know about how loose. Thought about poking near it to see if it moved. Started on the glass and has been resting in the sand since. It’s typically stationary. I never spot it moving.

I did take a google search of the upside down jellyfish, and it looks like that’s exactly what it is!! Thanks!

Do they sting corals, people, fish? Seeing that they are typically sand resters on the search.

Then congratulations are in order, one of the more unusual hitchhikers!

To answer your question, they are known to have a mild sting, strong enough to produce an itchy rash on human skin. But it's purely defensive, they don't have long trailing sweepers like more predatory jellyfish do. Instead they feed like photosynthetic corals, and spend most of their time on the bottom, soaking up the light for their zooxanthallae.

Personally i'd risk keeping it, as it's one of very few jellies that can actually be kept in a normal tank.

 

[onlyreefers]

Update. I now have 16 of them lol

 

[Gabbone]

I’d personally remove since they can bother corals and fishes.

 

[onlyreefers]

I’d personally remove since they can bother corals and fishes.

All new ones just float over into their little spot with the others and never move. They are always stationary and the livestock never try and nip at them or anything.

 

[dochoot]

Very cool

 

[Alexraptor]

All new ones just float over into their little spot with the others and never move. They are always stationary and the livestock never try and nip at them or anything.

They are actually extremely delicate and don't like being blown around by strong currents and can even be damaged if thrown against the rocks. My guess is that spot is an ideal sweet spot in your tank, for them.

Eventually though you may need to rehome them, as they can grow to the size of a dinner plate, and with 16 individuals? Well....

Honestly a bit envious.

 

[GlassMunky]

Update. I now have 16 of them lol

This looks like pulsing Xenia to me not jellyfish

 

[onlyreefers]

They are actually extremely delicate and don't like being blown around by strong currents and can even be damaged if thrown against the rocks. My guess is that spot is an ideal sweet spot in your tank, for them.

Eventually though you may need to rehome them, as they can grow to the size of a dinner plate, and with 16 individuals? Well....

Honestly a bit envious.

Thanks! I saw that they can get at least 2-3”, dinner plate would be great lol. The largest one seems to have stopped at about 2 inches. It seems like at least 1 new baby per week. I’ve got some local reefers I can give the extra to if things get crazy, and a little cycling 25g setup that I could dedicated for them. I’m a big fan. Fun to watch.

 

[onlyreefers]

This looks like pulsing Xenia to me not jellyfish

They are 1000% upsidedown jellyfish. If I were to disturb the sand a fluff them up into the air (water column), they will “swim” once in lifted up, and you can see their full jellyfish body.