Jellyfish: Adding One to Your Aquarium

In all the years that I have been associated with and mesmerized by the marine aquarium hobby, I have seen a myriad of exotic and diverse animals, which could be welcomed inhabitants in a marine aquarium biotope. Sharks, Sea Cucumbers, Nudibranches, Lionfish, Lobster and the plethora of beautiful coral. Yet another unique animal has found its way into the undersea world of the fascinating and entertaining marine aquarium hobby. The Upside down Jellyfish known as Cassiopeia is the best choice for those wishing to try their luck and be the talk of the town by incorporating a jelly into their bioload.

I know many of you are saying to yourself that jellyfish are the root of all evil, and a conglomeration of stinging tentacles that seems to dampen your vacation at the beach when you accidentally run into one of these hydroids. The most popular, and often times feared jellies, are the Portuguese Man-Of-War and the Box/Sea Wasp that can inflict excruciating pain, or worse, to divers and recreational swimmers alike. The Upside down Jelly is not like this at all!

Small size, unique personality combined with the lack of potent toxin that could cause complications to aquarists, the Cassiopeia jelly can provide entertainment and diversity to your marine aquarium that will set your tank apart from the norm. Of course their are precautions, husbandry and compatibility requirements that need to be realized and adhered to with the maintenance of an upside down jelly fish , but so doesn't any other animal. Being able to provide such key requirements as low water flow, small grain-sized aragonite sand, moderate light, communal tank mates and stable water parameters, should afford the jelly fish a great chance to thrive in your aquarium.

Cassiopeia jelly get their so-called upside down name because they spend most of their life in the upside down position. Found mainly in Caribbean and Western Atlantic waters, especially off the Bermuda Coast where the warm Gulf Stream provides a continuous flow of warm, nutrient rich water from the Caribbean. This type of jelly can also handle temperate water so a water temperature in the 60's should have little effect on the jelly and its survival. Upside down jelly hail mainly close to shore, in tide pools and inshore bays that provide sandy, muddy bottom areas that are ideal for the upside down jellyfish. Because the bell(body) of this jellyfish is very delicate and spends most of its Medusa stage of life on the bottom, soft benthic bottoms are very important to the health of upside down jellyfish. Areas with live rock, course shell and large grained sands increase the chances of the jelly's bell getting cut, injured or worse. The jelly pulses its body up and down on the bottom to provide water flow and possibility of disturbing and capturing a meal.

Upside down jelly fish live their lives upside down for very good reason. It enables their zooxanthellae, hosted in their mesoglea, to capture beneficial light from above and harness light through the photosynthetic process which ultimately provides nutrients to both the jelly fish's zooxanthellae and itself in the form of carbon. Their tentacles, which consist of four branched and unfused arms hosting nematocysts for both protective purposes as well as capturing small zooplankton that may become suspended in the pelagic areas of their environment.

The color associated with upside down jelly fish is normally a bluish, green to gray color. This coloration is a direct result of the zooxanthellae that resides within the jelly's body. The coloration can be modified somewhat, which may have to do primarily with the amount of sun light the jelly receives and the location where the jelly resides.

The Upside down Jelly is truly an unique animal that can find its place in the marine aquarium hobby from time to time. The fact that this animal remains small, is fairly hardy and very diverse to most of the other livestock found in your local pet shops, should warrant its place within the aquarium environment. Providing this animal with the small amount of husbandry requirements and ensuring that their are no boisterous invertebrates and fish within the tank and you should be able to experience the enjoyment and excitement of housing a jelly fish in an aquarium biotope.

http://en.wikipedia.org/wiki/Cassiopea