For most people, the only place they've seen jellyfish has been when the invertebrates wash up on the beach in a sandy, blobby mess, or bobbing about in schools by the pier. In larger cities, the local public aquarium might have a special exhibit of jellyfish, but the delicate nature of jellies and their tendency to get sucked into the plumbing have kept them out of the pet shops and the hands of budding medusaphiles ... until recently.
The Jellyfish Cylinder Nano uses a laminar water flow pattern that mimics the natural currents of the open sea and is designed to circulate the jellyfish without harm. It has an air pump and integrated mechanical, chemical, and biological filtration system in the base and rear as well as a multi-color LED light with remote control. The entire support system is designed to operate coolly, so the tank remains at room temperature.
Getting started with the Nano works on the ant farm principle. In other words, the tank kit comes first in one box and after it's all set up, you send off for the jellyfish. In the first box is the two-gallon (7.5 l) acrylic cylindrical tank and all the bits and pieces needed to make it work and to prepare the salt water for the jellyfish, as well as manuals to walk the user through the process and explaining how to take care of the sea creatures. In addition, Jellyfish Art provides exhaustive online resources and video tutorials to walk you through each step.
The latter is very important because we found that the biggest obstacle to setting up the Nano was a major case of nerves. It's not like we knew anyone who kept jellyfish as a kid, so there was a lot of "What the heck do I do now?" moments to overcome. Reading the manuals very carefully from start to finish and watching the tutorials was a great aid, and it also helped us to realize that setting up the Nano tank required some serious logistical thinking so that everything would be ready when the jellyfish arrived.
Mechanically, setting up the tank was very simple. The Nano is a cylinder with a viewing window on the front, and a baffle at the rear to set up the laminar flow and keep the jellies out of the filter. Putting it together was simply a matter of popping in the disposable filter bag, sticking the pump and the LED lamp to the transparent base, threading the tubing and cables, and attaching the tank to the base. In all, it took only about twenty minutes.
The next step was the salt water. Jellyfish Art says that the Nano can take pre-prepared salt water from a pet shop or aquarium supply, but we decided to use the pre-measured salt mix included with the kit. This required an extra investment in a food-grade five gallon (19 l) plastic tub to mix the salt with distilled water.
The pre-measure was a great convenience, though it would have been nice to have some extra on hand in case the salt content needed tweaking. The company recommends letting the water sit for 24 hours before measuring the salinity using the included hygrometer, but we found that waiting 48 hours produced a more accurate reading. The hygrometer itself turned out to be very cranky and needed careful filling and tapping to work properly.
Once the salinity is in the proper range, the water is transferred to the tank and a measure of the bacteria starter poured in to kick off a colony of microbes that feed off the jellyfishes' waste products. This was a rare instance of the manual being a bit vague as to the directions and we suspect that we added too much, though this seemed to cause no harm.
Once the tank was set up and the filter system running, we used the included voucher to go online and claim the three small moon jellyfish included with the kit. The company ships these for free and guarantees them for 30 days. However, US law prevents them from being shipped abroad. Tracking information is included, making it easy to make sure someone is available to sign for them and start the acclimation process.
Introducing the jellies to the tank turned out to be slightly comic. They arrived in an insulated box along with a month's supply of jellyfish food in the form of dried plankton. The jellies themselves came in a double plastic bag filled with seawater like fairground goldfish. Acclimating the jellies involved removing an equal amount of water from the tank, then setting the bag inside.
Over the course of an hour, measured amounts of water were transferred from the tank to the bag, so the creatures could adjust, then the bag was reversed and the jellies spilled out as the bag was removed. The trouble is, manipulating plastic bags containing three animals that look like plastic bags made it very difficult to keep track of them and one person had to count them out while the other handled the bag.
Feeding the jellyfish proved to be very simple. A measured quantity of food is placed inside a feeding pipette, which looks like a turkey baster. Water is sucked in from the tank, the pipette is plugged and given a good shake, then the mixture is squirted into the water. Several more squirts stir up the bottom of the tank where uneaten food may have settled previously. We didn't find much of the latter because jellyfish turn out to be surprisingly fast eaters.
Once everything was up and running, we found the Nano very easy to maintain. In fact, its spartan interior without toys, gravel, or plants, made it very easy to clean with a simple brush once a week before changing out a quarter of the old tank water with new. During the first water change, we learned that jellyfish require patience. On the first partial water change, we found them huddled on the bottom. At first we thought it was because the salinity was too high, but that turned out not to be the case. The jellies just needed 24 to 36 hours to readjust their buoyancy to a slightly different concentration.
Like any aquarium, the Nano does require some expenditure to run. Saltwater or marine salt mixture needs buying, as does food, filter packets, and bacteria maintainer. The company provides a starter supply of all of these, but this is only good for a month. After that, you need to buy the supplies separately or as a quarterly maintenance kit for US$50.00.
It's possible to get most of this on your own with a good deal of homework and the luck of being close enough to a saltwater aquarium shop, but we found that these are often unreliable in our neck of the woods if you need, for example, prepared salt water in a hurry and we found more than one that promised to mix a batch "tomorrow" several days in a row.
Overall, we found the Jellyfish Cylinder Nano to be surprisingly easy to setup and maintain – certainly more so than many conventional saltwater aquaria we've encountered. So far, the jellies seem in good health and spirits (if the latter can be said of a jellyfish), and watching them is relaxing and addictive with the LED light show providing an added dimension of entertainment as well as a nightlight. It's quite the conversation piece.
The only real drawback to the design is that the specially designed filtration system is made to avoid sucking up the jellies, but one will occasionally pancake against the water inlet baffle and need to be gently pushed away using the feeding pipette. While cleaning is easy, the small size of the tank makes it tricky to keep from bumping into the jellies with the brush provided, and the acrylic surface demands a "do not touch" sign to avoid fingerprints.