Can I keep Jellyfish at home ?
Yes and No, it depends on who you talk to. A few things for sure, you obviously need a source of jellyfish and you need a specific system to hold them, as well as, a regular supply of planktonic food.
The truth is that jellyfish are NOT easy to keep, and only advanced hobbyists should try it !
There are those who feel that public aquariums and academic type people are the only ones capable of maintaining jellyfish. This is true, as they have the resources and the knowledge. On the other hand, there are a few individuals who have, or are, perfecting the systems, foods, as well as, learning how to propagate or raise jellyfish in captivity. Midwater Systems has developed a custom acrylic jellyfish tank, called the Jelliquarium, and is working on holding systems used to keep these midwater collections and gelatinous organisms in suspension.
Until recently the only source for live jellyfish was to collect them yourself or public aquariums. In general, most public aquariums are prohibited from providing or selling them to anyone other than other academic institutions.
Lately though, there have been a few people who have either entered into the market, or have plans to enter that market, and offer various species of jellyfish, systems and food supplies for sale.
The jelly that is being most commonly raised is the Aurelia aurita species, or commonly called the Moon Jellyfish. The methods of raising these jellyfish are slowly becoming more perfected, although supplies are no where near marketable amounts.
Aside from the livestock supply aspect of owning a jellyfish tank, one needs to be aware of the specific requirements of that tank. Since jellyfish are physically delicate, are prone to flow with the current, are suspended by the current, and it's that current that brings them their food, their tank has to be specially designed to meet all those needs. The tank is called a Kreisel.
A Kreisels design is one in which there are uniquely designed inlets and outlets for the water, as opposed to a single inlet and outlet for water. It has to be introduced in so that it is a gentle tumbling type flow and keeps the jellyfish suspended. It has to be drawn out in a similar manner that it does not 'suck' the jellies into the filter system. The basic idea I think of is similar, in some ways, to your clothes dryer. Water ( as opposed to hot air in the dryer ) is introduced around a perforated or specially screened cylinder, and it causes that water to gently circulate its inhabitants. Likewise the water leaving the kreisel needs to exit in a manner that does not take the jellies with it.
Aside from the design of the jellyfish tank is its filtration. This type of filter is very similar to a coral reef tanks. It should involve surface skimming, mechanical and chemical filtration, as well as, a effecient biological filter. It would also be a good idea to incorporate a protein skimmer too. Overall water quality is paramount !
In addition to the tank and its filtration Moon jellyfish require cold water. Since they live in waters that range from 55 to 65 degrees you WILL need a refrigeration unit.
Ok, so now you have the jellyfish, the tank with its special design, and have incorporated the proper filter system and chiller unit....what are you going to feed the jellyfish ?
In nature, jellyfish ( Aurelia species for the sake of this article ) feed on plankton. Fortunately enriched brine shrimp, shaved mysis shrimp can be the substitute for plankton. Recently a product called Cyclopeeze has been introduced as a substitute food source. Did I also mention that the jellyfish require MULTIPLE feedings on a DAILY basis ?
One other thing to mention, lighting. Since jellyfish ( Aurelia ) dont require light, the only illumination needed for the tank is so that you can see the jellyfish. This is a good thing as it minimizes the number of times you have to place your hand into that tank with COLD water and those creatures who sting
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