Frequently Asked Questions

How do I prepare sea water?

Preparing suitable seawater is one of the most important part of jellyfish keeping. When you mix seawater please prepare

  • An “aquarium use only” 1-5 gallons bucket or container
  • Small air pump, airline hose and air stone
  • RO/distilled water (Please avoid using tap water)
  • Jellyfish-safe aquarium salt (we recommend using our jellyfish salt)
  • Hydrometer


Procedure (making 4.5 gallons of seawater)

  1. Add 4.5 gallons of RO/Distilled water to a bucket. Distilled water is available from supermarkets. Please avoid using mineralized water or tap water.
  2. Add 500g of jellyfish salt slowly as you are stirring the water (Salt can get hot do not touch)
  3. Keep stirring the water until most of the salt crystals disappear.
  4. At this point, the water will look still cloudy. Connect the air stone, airline tube and air pump, and put the air stone into the bucket. Keep aerating the water for at least 24 hours. Make sure the air pump is placed above the water level, so the water will not get siphoned when the air pump stops. It will be good to put a lid on the bucket to avoid salt dispersing around the bucket while aerating.
  5. Measure the salinity of the water with your hydrometer or reflectometer. It should measure around 28ppt (1.021sg). Jellyfish thrive well in the salinity range from 25-32ppt (1.019-1.024sg). Adjust if it is out of range by adding more water or salt. Be sure to flick or tap the hydrometer to remove any bubbles from the reader arm as bubbles can give an inaccurate reading. If you are having constant problems with hydrometer, consider investing in a refractometer or a digital salinity checker which are more accurate than a hydrometer.
How do I do a water change?

Regular water changes are required to maintain the water parameters in your aquarium in appropriate range. The volume of water change each time will depend on the number of jellyfish in your aquarium and how much you are feeding, but we recommend 10-20% every week.



  1. Stop the pump (and heater/chiller if you have one)
  2. Remove 10-20% of water from your aquarium slowly using a jug
  3. Add prepared seawater into the filtration compartment. Please make sure that the salinity and temperature of new seawater are not different from your aquarium seawater
  4. Turn on the pump (and heater/chiller if you have one)
  5. When pump is turned on, it releases some air bubbles into the aquarium. In case the air bubbles are caught by jellyfish, gently put them upside down and remove the air bubbles from their bells.
How to introduce jellyfish to my aquarium?

When you receive your jellyfish, you need to acclimatize them to the new water condition. Acclimatization is a process of matching water parameters such as salinity, temperature and pH as close as possible between the original water the animal was in and the new water the animal is moving into. Failure to do this shocks the animal possibly to death.



  1. When you receive your jellyfish, carefully check the condition of the jellyfish before opening the original bag. If you find them damaged or dead, take pictures of them and contact us asap.
  2. Once the jellyfish are confirmed to be in good condition, open the original bag and put it in a jug or bowl which can contain at least 3 times the volume of water in the original bag. Once the original bag containing jellyfish is placed in a jug/bowl, pull the bottom of the bag slowly to release the jellyfish into the jug/bowl. This way, you can avoid the risk of jellyfish getting air bubbles
  3. Once the jellyfish are released in a jug/bowl, start the acclimatization process. The best way to do this is using an airline tube (drip method). Put one side of tube to your aquarium, and put another side of tube to the jug/bowl with your jellyfish. Connect a syringe to the jug/bow side of tube and suck water. This will start siphoning water from the aquarium to jug/bowl. Add a small valve or tie the end of tube to adjust the speed of water dripping into the jug/bowl. Ideal speed will be a couple of drops/sec. Do this for at least 30 minutes until the water volume in jug/bowl become 3-4 times of the original volume. If you do not have airline tube, you can use a small jug to add water from the aquarium to jug/bowl a bit by bit over 30 minutes to achieve the same effect.
  4. After the acclimatization process completed, jellyfish can move into your aquarium using the fine mesh net. The water in the jug/bowl can go back to your aquarium until the water level of the aquarium become suitable.
  5. In case jellyfish catch air bubbles in their bells during this process, gently put them upside down and remove the air bubbles from their bells.
What temperature should I keep my aquarium at?

The suitable temperature for jellyfish varies depending on the species. Please refer to the optimal temperature shows in each jellyfish page.

What should I feed my jellyfish?

There are two types of jellyfish in terms of their feed. One type is planktivorous jellyfish, such as moon jellyfish, flame jellyfish and blue blubbers, which feed on small zooplankton. Another type is jellyvorous jellyfish, such as sea nettles and lion’s mane jellyfish, which feed on other jellyfish or small shrimps or fish. In captivity, the best food we have found so far for planktivorous jellyfish is live baby brine shrimp. Frozen baby brine shrimp can be fed alternatively, but more water change will be required as they decompose quicker than live baby brine shrimp. We also suggest our Medusa-G food as alternative food but they also require more water changes compared to feeding live baby brine shrimp. Feeding jellyvorous jellyfish is easier, as they can feed and grow well on feeding frozen adult brine shrimp, mysids or chopped up fresh seafood such as clam, mussel and prawn. LRS’s Fish Frenzy is also a good food for jellyvorous jellyfish.

How are the jellies shipped?