You may notice your jellies starting to curl up and move their bells in an erratic, clockwise or counter-clockwise rippling fashion instead of a normal pulse. We like to call this symptom “the Jellyfish Jig” and it indicates trouble in your tank.
The cause is linked to nerve damage in your jelly, which can arise is several ways.
-Your tank pH spiked suddenly: If you’re having pH problems in your tank, you have to adjust the chemistry slowly. If you add a ton of buffer or change too much carbon all at once, it may bring your pH up too quickly. Jellies always need to be acclimated to new conditions, even within the same system, so even though your goal is a pH of 8.0-8.2, you don’t want to get it there in a few minutes.
-Your jellies experienced sudden temperature change: If you took your jellies out of your tank for a major cleaning and dumped them right back in, or if you did your weekly change with some water from your refrigerator, that can have serious consequences for your jellies. Again, they require stable conditions to be happy and healthy. Always be mindful of temperature when your jellies are going to experience changes in their water.
-Your jellies’ food is too acidic: If you use shelf-stable jellyfish food, or you allow your frozen or refrigerated food to spoil, it can be highly toxic to your jellies. Live food is always best, frozen enriched food is a close second, but using anything below that in quality poses the risk of poisoning your system.
-Your jellies were stuck to the bottom or side of your tank for too long: If your tank flow is dialed down too low or your jellies are getting too big for their system, you may see them start to get stuck to the walls of their space like a suction cup. When this happens, they can no longer exchange nutrients and gases with their environment, so they will start to degrade. Not to mention, they will continue attempting to bell, which can lead to them pulling out their own oral arms. If you see them stuck to the sides or bottom, gently squirt some water at them with a clean turkey baster from a diagonal position to try and lift them off (be sure not to squirt all the water out because that can create problematic air bubbles). If that won’t work, gently nudge the edge of their bell with the end of the baster or another clean, rounded object.
In most cases, your jellies won’t be able to recover from this condition, but you can at least prevent it from happening to future jellies or any survivors.
Low pH can have adverse effects on moon jellyfish over time, especially when it drops below 7.6. This problem is common in aquariums with filtration systems that don’t allow for adequate aeration or disturbance of water.
The optimal pH for moon jellyfish is 8.0-8.2. As pH lowers below this range, the water becomes more acidic and harbors excess carbon dioxide (CO₂). If prolonged, the lower-than-optimal pH can cause pitting in the bell, eversion, and bell shrinkage in jellies. Although moon jellyfish are commonly described as being “hardy” and “tolerant” of extreme water quality levels, too extreme can and will eventually cause them damage.
A damaged jellyfish after living in <7.6 water. Photo from our Cubic Orbit 20 Aeration video.
Filters that allow for splashing and rapid movement of water through them introduces oxygen to the system, keeping the pH up by steadily off-gassing that harmful CO₂. When filters are completely submerged in water, the rate at which the water is moving through them is little to none and can negatively affect both the water quality of your aquarium and the beneficial bacteria that you’ve worked so hard to grow during cycling. If the water isn’t moving through the filters, then the filters are doing nothing to clean the water. Adequate and efficient water flow through the filters is necessary for both the water quality and beneficial bacteria to stay in tip-top shape.
Luckily, this is an easy fix!
There’s all kinds of water conditioners, additives, and buffers on the market today that are specifically made to raise pH… for normal fish tanks, however. Since jellyfish are 96% water, they are a bit more sensitive to the chemical makeup of water than normal saltwater fish. So, adding in a bunch of chemical powders and liquids, especially into a small desktop jellyfish aquarium with less than 10 gallons of volume, isn’t always the best idea and can cause more harm than good! So, don’t do it!
Instead, we recommend the following tips to help keep your pH optimal:
Adding a bubbler is an easy and worry-free fix to raise pH. Bubblers (also known as aerators) constantly introduce oxygen to the water via bubbles. Most aerators include a valve or dial to alter the rate of bubbles giving you more control, which is even better.
It’s best to place the bubbler in the filter compartment, away from the pump, and as far down to the bottom of the tank as possible. This way, the bubbles are not being sucked into the pump and have a longer path to reach the surface, releasing a bit more oxygen into the water.
Note: You do not need an air stone, if one is included. These will only create smaller, erratic bubbles that have a higher chance of getting sucked up by the pump and into the jellyfish area – which you don’t want!
Always make sure your new saltwater has a pH of 8.0-8.2. This will help raise the overall pH of your aquarium and keep it up through weekly water changes.
We experienced this problem when working with the 6 gallon Cubic Orbit 20 jellyfish aquarium, as you can see in the video below that we put together some time ago.
Technically called “eversion,” it’s defined as the process of turning inside-out. In jellyfish, eversion is when the outer perimeter of the bell has flipped up and over the top of the bell, creating a saucer or cup-like body shape. The oral arms of the jellyfish also hang down and are not tucked up under the bell, as per a healthy jellyfish.
[Note: “eversion” is when the bell is flipped inward; “inversion” is when the bell is flipped outward. “Inversion” is commonly used instead to describe this process in jellyfish.]
Common Causes
Here are things that can cause jellyfish bell eversion:
Malnutrition leads to thin and weak jellyfish that are prone to flip
Flow rate is too high causing the jellyfish to spin like socks in a dryer
This prevents jellyfish from belling or swimming naturally, which means they also are not eating properly, ultimately leading to malnutrition
Flow rate is too low and the jellyfish are unable to bell properly due to the lack of “support” they get from the water movement
Belling problems always lead to eating problems—if they can’t bell properly, they can’t eat well, causing malnutrition (again) and creating thin, everted jellyfish
Physical damage that occurs when a jellyfish becomes stuck to the bottom or side of the tank for over an hour, damaging their bell
Luckily, these are all fixable issues!
Solutions
Happy and healthy jellyfish should have rounded bells
Here’s how you can prevent eversion from happening:
Feed only nutritious, neutrally-buoyant foods on a daily basis to maintain proper cell growth and function
Adjust the flow rate just enough to keep the jellies off the bottom of the tank, but not so much that they are being propelled around the tank.
When trying to find the perfect flow, adjust your flow control valves and wait 20 mins between each adjustment to watch for a difference
Want to see an example of what proper flow looks like? Check out a few of our jellyfish aquarium videos on YouTube.
Maintain the proper flow rate and the jellies will not have the opportunity to get stuck for long periods of time
Read more about the physical differences between HAPPY (healthy) and SAD (unhealthy) moon jellyfish on our Jellyfish Troubleshooting page.
Although it’s quite rare, sometimes our jellyfish can have a rough transit experience resulting in them arriving in less-than-perfect condition. We take every precaution to prevent this from happening by making sure our shipping methods are as safe and protective as possible, but there still remains a bit of risk when shipping any live animals. Once they leave our doorstep, we unfortunately can’t control how they are handled by the shipping carriers.
They can arrive with holes or tears in the bell, as shown in the picture below…
Picture submitted from one of our customers.
…which is not what you want to see when opening up your bag of jellies! You want to be joyous and excited to get them acclimated into your jellyfish tank!
Gif courtesy of our EON Instructional Video Series.
Most of the time, damage during the transit process is caused by the jellyfish becoming suctioned to a side of the bag once the package is at rest. When the package is picked up and begins to move again, the jellyfish becomes forcibly un-suctioned, resulting in them being torn away from the bag. It happens, but the good news is jellyfish are very good at repairing themselves!
“How do I know if my jellyfish is dead?” Good question. 99% of the time a jellyfish arrives in less-than-perfect condition, it’s not dead. Unless the jellyfish in question is completely mangled, balled up, or disintegrated to pieces, it’s not dead and there’s a very good chance it will get better once acclimated with good saltwater and good food.
Here’s what to do after your jellyfish are delivered:
Inspect the box and inside styrofoam for any damage. Take the bag of jellies out of the styrofoam box and read the Acclimation Instructions and Return Policy label on the lid.
Before opening the bag, observe your jellies by slowly turning the bag around to get them moving. Observe the overall condition of their bodies. If you find a jellyfish with a hole or tear in the bell, don’t freak out. Instead, take a picture of the jellyfish in question (following the instructions on the label) and email us to see if it’s a serious issue. It’s easiest to grab a photo if you hold the bag up in front of a light.
Observe their activity level. Most of the time, new jellyfish will arrive belling and ready to come out of the bag. Sometimes they can arrive sluggish, exhibit slow belling, or with retracted tentacles from the rare case of being excessively tossed around during transit. There’s nothing to worry about. Once acclimated to clean, fresh saltwater, they should perk up quickly!
***Please note: After proper acclimation, happy and healthy jellyfish do not need more than a few hours to become fully comfortable with their new environment. If your jellyfish is not belling or slow-moving for longer than 24 hours, there is potentially an issue with the jellyfish or water chemistry of the aquarium. It does not take 1-2 weeks for jellyfish to get used to the new tank water; this is a misconception.***
The video below shows the condition moon jellyfish should arrive in. Round, open bells. Untangled tentacles. These are definitely happy and healthy jellies!
If they do, I’m sorry to hear that, but don’t despair just yet. Once you determine the problem & fix it, the jellies can bounce back and repair themselves in no time! Here are the top 5 reasons jellyfish will start to fall apart…
1. Improper filtration and/or incomplete cycling of your filters.
2. Ammonia spike.
3. Not Acclimating your Jellyfish Properly
4. Improperly making up your saltwater
5. Heavy metal contamination.
1. Improper filtration and/or incomplete cycling of your filters.
If you haven’t properly cycled your tank, then you most likely have toxic levels of ammonia and/or nitrite in your water. This can happen when you initially set up an aquarium and add jellyfish (or any life forms, for that matter…this is not a jellyfish specific issue, but a standard fish or coral tank issue. You must take the time to properly cycle your aquarium no matter what animals you choose to keep in it). Once jellyfish are added to the tank, they begin to produce ammonia. Once ammonia starts to build up, you need to have a way to eliminate it. This is why proper filtration is important. A properly filtered aquarium will have a biological filter in place, which will remove the toxic ammonia and nitrite by way of the beneficial bacteria that populate the filter media (i.e. bio balls). If you do not have beneficial bacteria actively removing the ammonia and nitrite, then the water becomes toxic and the jellyfish will soon begin (within 2 days) to disintegrate like the pictures demonstrate.
Ammonia & Nitrite levels demonstrating the middle of a nitrification cycle. This is a very toxic situation. Jellyfish will fall apart if subjected to these levels of toxicity.
2. Ammonia spike.
Why are you having an ammonia spike even after you’ve already cycled your tank? An ammonia spike can occur if you stopped feeding your tank for any reason. Sometimes folks let the aquarium go down, or let it run without any animals in it for awhile like if they go on vacation or take some time away from keeping jellyfish, or they don’t have jellies in it for several days for whatever reason. This leads to an ammonia spike because your beneficial bacteria in you filter box didn’t receive any ammonia to eat—your system wasn’t creating any ammonia because you had no jellyfish in it & subsequently weren’t feeding any jellyfish. This means the beneficial bacteria went with out food (ammonia) and starved to death. So, if you then add jellyfish to the tank when you get back from vacation (or whatever), there is no beneficial bacteria available in the filter box to eliminate the toxic ammonia & you experience an ammonia spike and shredded jellyfish as the pictures show.
If you do go on vacation, or take more than 3 days away from having jellyfish in your tank, you can alway place a small, 1/4″ piece of raw fish or shrimp in the filter box to continue to decompose and create ammonia for the beneficial bacteria to feed on while you’re away. When you return, always take an ammonia reading and remove the piece of raw fish or shrimp before adding new jellyfish to the tank. Make sure your ammonia and nitrite levels are at zero before acclimating any new jellyfish into your tank.
An ammonia spike can also happen if you interrupted the cycling process by cleaning the tank, changing any mechanical or chemical filters, or conducted any water changes prior to the tank completely finishing its cycling process. Do not interrupt the cycling process. I know it’s tempting to want to get the sides & bottom of the tank clean. The algae growth can be unsightly, but remember, you are creating a living environment from a static one. Life can be messy! Let nature take it’s course and be patient– I know it’s hard, but it is necessary. You can clean the tank all you want after the cycling process is over! If you interrupt the cycle, it can take almost 3 times as long to get it back on track an in a non-toxic state. Be patient. It’s worth the wait!
3. Not Acclimating your Jellyfish Properly
You are receiving jellyfish that are coming from a pristine environment. When you receive a shipment of jellyfish, the water quality parameters are most likely different from yours. You must take the time to acclimate the jellyfish in the shipping bag to the temperature of your system. After 10-15 minutes of floating the bag so the temperatures equalize between the bag and your tank water, acclimate them to your water quality (pH, salinity), by conducting small water changes in the bag over 45 minutes to 1 hour. Don’t take all night doing this step. The jellies need to get out of the bag and into a moving environment. Acclimation shouldn’t take more than 1.5 hours from start to finish. If it is taking longer than that, then there is another problem at hand that needs to be addressed.
4. Improperly making up your saltwater
If you are making up your saltwater with tap water, your jellyfish will fall apart. Tap water has heavy metals in it that the jellyfish cannot tolerate. You must make up your saltwater with RO, RO/DI, or distilled water for it to be safe for jellyfish, much like a reef tank.
If you are not aerating your saltwater for at least 24 hours in a bucket with a small submersible pump, then you most likely are adding undissolved salts to your tank. The jellies don’t do well with undissolved salts. Please read our blog post that covers this topic in depth: “Problem with Your Jellyfish? Undissolved Salts Could be the Culprit”
5. Heavy metal contamination.
Do not use metal utensils or tools with your saltwater jellyfish aquarium. Only use plastic tools. Always wash your hands before dealing with your jellyfish or handling the jellyfish food. Zinc, brass, lead & petroleum products (sometimes found in soaps and lotions) will add heavy metals to your system. The jellyfish will fall apart if you introduce them into the water. Also, I should mention that aquarium heaters can get old– moreover, their seals can get old and crack. This can allow water to leak into them where the metal heating coil is located and other metal parts. If you have an old heater, check it for any visual signs of rust on the heating coil. If you see rust, throw it away and purchase a new one.
Send us your problem jellyfish pictures and we’ll diagnose the problem and tell you how to fix it. We’ll also write a new blog post about it so we can inform and help others that may be experiencing the same problem!
Send your pics to moonjellyfish.com@gmail.com
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Have you had an unusually long cycling process? Are your new jellyfish shrinking fast even after the tank finally cycled?? Please read our blog post next week for answers.
Large 10″ diameter Moon Jellyfish– This jellyfish has been raised in one of our customers tanks from 3″ diameter to 10″ diameter solely on our Frozen Jellyfish Food (feeding once a day).
Are your jellyfish shrinking, getting thin and flattening out???
Here are 5 reasons why that might be…..
1. Feeding Non-nutritious food
One of the most common problems when keeping jellyfish is keeping them properly fed. Without a consistent supply of nutritious food, they will become weak and thin. Malnutrition causes listlessness and infrequent belling or pulsing, leaving you with inactive jellyfish that just float around the tank like pieces of tissue paper. Not pretty. Not elegant. Not fun! Your solution is to feed them jellyfish food that is nutritious & to feed them the proper amount. There are a lot of feeds on the market for fish and corals and you may think that they will work for jellyfish. Not the case. Reef Nutrition has some amazing feeds for filter feeders and some of what they have to offer are good supplements for jellyfish, but not strictly meant for a main food source.
Jellyfish are not goldfish & you cannot simply sprinkle some food in every other day or so. They need to eat each day and they need to get a good amount into their systems with each feeding. See our blog post Knowing How Much to Feed Your Jellyfish for guidelines & pictures of what a well fed jellyfish looks like. Without enough good food to eat each day, they will become thin and lazy.
3. Your Flow is too High—or Too Low.
If your jellyfish aquarium has adjustable flow, you may need to fine tune it. If the flow is too high, the jellyfish may not be able to keep the food on their tentacles as they whiz around the tank and this means they are not ingesting the food. This leads to underfed jellyfish, which leads to lazy and shrinking jellyfish. The same goes for low flow. If the flow in your tank is so low that the jellyfish cannot properly bell and keep themselves suspended, then they will not feed properly. Again, this leads to malnutrition and shrinking jellyfish. Jellyfish need to bell efficiently in order to move fluids and food into and throughout their system.
4. Your Jellyfish Aquarium is Not Cycled
If your aquarium is not biologically cycled then your water quality is toxic (you have ammonia and/or nitrite levels above zero) and the jellies will be stressed because of it. Jellyfish are 96% water, so if your water quality is suffering, so are your jellyfish. They will not eat much, if at all, and this leads to shrinking jellyfish.
5. Your Salinity is Too High
When your salinity is too high, the jellyfish will cease to eat. Keep your salinity in check–everyday if necessary–so your jellyfish can feed properly without the stress of spiking salinity levels. If you haven’t yet read our blog post about hydrometers and the inaccurate readings they can give….read it now. The plastic hydrometers on the market tend to have variable readings. Have your hydrometer tested at your local fish store to be certain that yours is giving you accurate readings. Again, if your jellyfish are not getting enough food each day, they will shrink.
And a word about vacations, weekends & days off from feeding….
If your jellyfish are healthy and being fed normally and on a regular basis with nutritional jellyfish food, then you can safely get out of town for the weekend. They will be fine given they have full stomachs 5 days out of 7.
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