Jellyfish Ailments, Diseases and Troubleshooting

Inversion

 

What is it: As the name might suggest, this is when the bell of a jellyfish turns inside out. Besides water, jellyfish are mostly made out of protein. Just like scrambling an egg, the proteins in a jellyfish can also become "scrambled" when conditions aren't ideal. The most common cause of inversion is exposure to excessive heat or a sudden change in temperature. That second part is important- even if your jellyfish is being kept within their ideal temperature range, sometimes a rapid change can still cause them to invert. Other causes of inversion can be: high ammonia or nitrites, pH swings, or overall poor water quality.

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How to Identify: Jellyfish will turn inside out like an umbrella caught by the wind. Note that inversion is different than bell flattening. Although a flat bell can eventually lead to inversion, jumping the gun and treating it as inversion can do more harm than good. 

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How to Fix it: inversion has a better prognosis if caught early. Easier said than done, I know. The trick to treating inversion is coercing the proteins and collagen to form back to the correct shape. This can be done manually through a process often referred to as manually flipping. To do this, take one finger and place it under your jellyfish in the center. Start raising your jellyfish up towards the surface of the water. Slowly and gently raise it slightly out of the water. The jellyfish's bell should flip back under its own weight. This process may need to be repeated several times for it to "stick". Just keep an eye on the jellyfish and keep flipping it back.

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Balling

 

What is it: The edge of the bell curls up until the affected jellyfish is more ball like. Eventually the jellyfish stops pulsing. This effect is more obvious in saucer shaped jellies, such as a moon jellyfish, but can happen to any species. Often caused by a response to some foreign chemical in the tank. For public aquariums that bleach their holding systems, this is often a sign of bleach poisoning. Cleaning sprays used near the aquarium, chlorinated water etc. are all possible causes. Balling can also be caused by irritation from the jellies bumping into something. Excessive algae buildup, hydroids, polyps and/or sharp/rough objects in the display tank can also be the culprit. 

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How to Identify: Bell curls inward, giving the rim a rounded appearance. 

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How to Fix it: Like Inversion, balling has the highest chance of recovery if caught early. Once the jellyfish stops pulsing, there's little chance of a full recovery. The first step is identifying the cause and resolving it. If you're unsure of the culprit, give the tank a thorough clean and do a large water change (50% or greater). If the balling is caught early, the jellyfish may make a recovery. However, if the jellyfish is no longer pulsing its likely there is nerve damage. Despite this, the jellyfish should continue to eat and may live for several weeks or months longer- it just won't return to quite the same shape or form it was before. 

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Taco Belling

 

What is it: The name honestly says it all! The jellyfish's bell will curl in half, forming a taco shell shape. This is often caused by a hole in the bell near the center of the jellyfish or malnutrition. 

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How to Identify: Similar to Balling but more distinctly folded in half. Can present as folding inward or outward.

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How to Fix it: Verify if there is a whole in the bell of your jellyfish. The folding may just be a mechanism to close and heal up the hole. If that's the case, observation is best. The hole should eventually heal and the jellyfish will regain most or all of its previous shape. If no hole or bell damage is present, the likely cause is malnutrition. This is fairly common in moon jellies exceeding 6". Try incorporating foods with high protein and fat content, like PE mysis shrimp. This will help thicken their bells and in time their shape should improve. 

 

Bell Rot

 

What is it: Bell rot is fortunately a disease rarely encountered anymore. A bacterial infection that causes the jellyfish's bell to rapidly deteriorate, leaving only the arms behind. This disease typically impacts wild caught jellies, especially sea nettles, but is almost never seen in captive raised specimens. Captive bred jellyfish are used to living in aquariums and occasionally bumping into things. Additionally, captive bred jellies are raised in a pathogen free environment, limiting the introduction of disease.  

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How to Identify: May start as a small hole or laceration that grows larger in a matter of hours. Regular holes or cuts in the bell typically stay around the same size and heal up in a few days. 

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How to Fix it: This disease acts extremely fast and there's not much that can be done. Some studies have shown potential success with antibiotics but its still not clear if bell rot is caused by a singular species of bacteria. The best course of action is to quarantine the affected jellyfish to avoid potential spread. 

 

Bell Flattening 

 

What is it: 

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How to Identify: 

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How to Fix it: 

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