Not pulsing and rounding out

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Not pulsing and rounding out

Postby 32jj32 » 14 Feb 2017, 19:15

Hello everyone,

I am having problems again. This time I have no idea whats going on. Last week I suddenly noticed that my jellyfish stopped pulsing completely. So I tested the water and everything seemed to be perfect. Since then I also noticed their bells are shrinking around the edge and getting more round almost like a ball. Just today I noticed that they all have holes on the bottom of the bell in the middle of all their stomachs. So I'm thinking it has to do with some bad food that I fed them. Lately I've just been strictly feeding them freshly hatched brine shrimp. I did notice that when I fed the last batch of brine shrimp that there was some cloudy material in the solution with the brine shrimp. Could rotten food cause this issue? Any other ideas on what might be going on?
Posts: 4
Joined: 28 Dec 2016, 18:03

Re: Not pulsing and rounding out

Postby 32jj32 » 23 Feb 2017, 18:00

Update: I have not heard back from anyone on this issue which makes me think something weird is going on. The jellyfish still aren't pulsing but are still taking in food somehow. Just today it looks like they are starting to fall apart. Testing is still showing that all water parameters are in a perfect range. Is this what happens when jellyfish die of old age?
Posts: 4
Joined: 28 Dec 2016, 18:03

Re: Not pulsing and rounding out

Postby Bakesalee » 01 Mar 2017, 08:12

Could you take a few photos?

-What is the pH?
-Did you make any changes whatsoever (water changes, etc.)? If not, when's the last time you did?
-What's the salinity of your tank water? What's the salinity of the "fresh" water that you add during water changes? The tank must not deviate over 3 points in salinity before/after change (example 1.027 to 1.024 would be the most extreme change)
-How many PPM of Nitrate?
-What's the temperature of the tank water? Is the temperature stable in your house all day long?
-Approximately how many days ago was it that your jellies looked healthy, before this?
-When you make water changes, what percentage of the water do you change?
-Do you have an air pump?
-What do you feed them? How long has this supply been in use? If liquid (Reef Nutrition), is it kept refrigerated?
-Is the speed of the water movement too fast?
Posts: 6
Joined: 23 Jul 2016, 21:17

Re: Not pulsing and rounding out

Postby DutchJelly » 11 Nov 2017, 18:53


I currently have the same issue.

Tho This all happend in a 10 minute time frame.
Ive been keeping them for a week and a half and so far they seem to be doing excellent.

Ive got 2 moon jellies and on arival one had a small hole and tear.
Once acclimated he was able to restore fully within 12 hours (amazing creatures!)

Now I just fed them and within 10 minutes they stopped pulsating all at once.

An other thing that happened was I saw a brown substance in the tube leading to the intake
Without thinking I squeezed the tube and it release a few food sided particles of this substance into the tank
For the last 30 minutes I’ve been observing them.

-they seem to discharge the food inside of them
-it’s goes with a sticky white substance
-the oral arms are tucked instide the bell

All water parameters are in range tho ph is a little low so started airing the water again.
I’ve this for the last few days and that raised it.

Are they dead? And what’s the best action to take from here?

I’m a little confused because what it happens so quickly, really need some advice and a hug :)
Posts: 1
Joined: 11 Nov 2017, 18:27

Re: Not pulsing and rounding out

Postby jellykawai » 26 May 2018, 14:07

Hey! I had the exact same thing with my blubber.
There are many things that could cause this but for me, I had 2 separate cases.

1) One time, jellyfish stopped pulsing and was literally looking like a ball for a week.
Water quality was fine and I was confused why this was happening, but I read somewhere that jellyfish prefers low salinity.
So even though my salinity was 1.025 which is bang in the middle of recommended 1.024-1.026, I added RO water to make it 1.022-1.023, then jellyfish started to uncurl within an hour.
He hasn't curled back since.

2) Another case is probably irrelevant to yours because it only lasted for an hour or so.
I was target feeding the jellyfish and that would cause one particular jellyfish to curl and stop pulsing.
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Joined: 26 May 2018, 13:52

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