Review: Orbit 20 Jellyfish tank


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 Not a fan of black? Simply buy a different trim for your jellyfish tank, pull it off and replace... Not a fan of black? Simply buy a different trim for your jellyfish tank, pull it off and replace...
 Not a fan of black? Simply buy a different trim for your jellyfish tank, pull it off and replace... Not a fan of black? Simply buy a different trim for your jellyfish tank, pull it off and replace...

Nathan Hill plays with this new aquarium from Cubic, designed for jellies.

The last time I reviewed a jellyfish tank is going back a few years now, and I loved the thing. That was also a Cubic model, the much larger Pulse 80, and at that time the only reservations I had were the price, and the ease with which the tank could be scratched. 

The Orbit 20 is smaller, sleeker, and wouldn’t look out of place on the set of Tron. I’d say it has smooth lines, but pretty much everything is curved in a gloriously circular design. 

It’s rounded for a reason, and that reason is flow and circulation. Jellyfish break easily, especially when they collide with anything, and so for decades the desired outcome by designers has been a tank in which the inhabitants contact nothing. To do this, they employ the ‘kreisel’ system, a German word that translates as ‘carousel’. The kreisel is a method rather than a particular product, and involves pushing water around a drum design, sometimes perforated, sometimes not. The idea here is that as the water rotates, multiple vortices or inflows at the edges keep the jellyfish pushed away from them. The inhabitants end up suspended in the central parts of the water column, while water flows in, around, out and through a filter. It’s a simple design that’s a beast to fine tune and get just right.

Providing the flow for this purpose is one of the dinkiest pumps you’ll ever witness — it’s not even 4cm across the longest stretch, and connects up to a tube that feeds a single spraybar. That doesn’t mean you can see the pump, because it’s hidden between the ‘inner circle’ where the jellyfish go (the clear bit) and the ‘outer ring’ where the hardware lives. 

The Orbit 20 requires some input from the owner. With the pump in place, you need to tweak the inline valve until you have the desired flow. Be advised that this will involve some faff, but it’s a necessary evil. Too slow and your jellies will bounce around the edges like a bad game of air hockey. Too fast and they might as well be in a blender. 

Filtration is entirely hidden from view in the outer ring. You’re supplied a mixture of porous biomedia that looks like lemon bonbons, and a chunky doorstep of mechanical foam. How often you’ll be cleaning these will depend on stocking density. Jellies are messy creatures, with their demands for repeated plankton-sized feeds, and as the efficiency of the set-up relies on controlled, constant flow, you’d do well to keep on top of that foam. Getting the biomedia back out should you need to is ‘awkward’ if you want to keep the tank running, because it falls to the bottom of the circular design. If you happen to have bones like most humans, you might find them somewhat prohibitive during retrieval. 

You need to top the tank up regularly anyway, so get used to looking at the filter when you do. If the water level drops, you lose your overflow, and by extension pretty much everything else. 

 The LED lighting above the tank offers a spread of colours. The LED lighting above the tank offers a spread of colours.

Lighting is incorporated, in the form of a controllable LED grid built into a removable hood. You can have white if you want white, but otherwise you can select from a range of red, green, blue and yellow options using the supplied remote control. You can go full party mode with strobes and all sorts, if that’s your gig. The jellies won’t really notice, what with their lack of advanced eyes. 

One pleasant feature is that you can change the ring trim on the front and back. Mine came with black as standard, but for £24.99 you can also get a red or a white option. On the downside, the magnets embedded in my trim weren’t sealed 100% and with a little rough handling became dislodged, needing gluing back into place. 

Rough handling is something to avoid if you want longevity. The construction is acrylic throughout, and that means that even a surly bumblebee could possibly scratch it if it wanted to. Small scratches can be rubbed out — I used to do it all the time with Brasso — but a big gash would be trickier. Be gentle. 

 A whole host of extras are included: remote control for lighting, feeding baster, hydrometer, pump and adaptor. A whole host of extras are included: remote control for lighting, feeding baster, hydrometer, pump and adaptor.

You also get some sundry bits in the package, including a hydrometer. Sites selling the tank suggest you get a swing-arm type, but my own was a good old fashioned, bobbing beer-style hydrometer (which I prefer). Getting specific gravity right is essential, as it affects jellyfish buoyancy. Too low and they’ll sink like the Titanic. Too high and they’ll each bob like a Portuguese man o’ war. 

There’s also a feeding baster (think turkey baster), so you can target feed your copepods/Artemia/whatever, as well as a siphon tube with hand-powered starting pump. It’s a small bore, which means you’ll not be dragging your jellies out in seconds, and you might be using it frequently — the minimalist nature of the design will be quickly ruined by a smattering of decaying ‘ook’ on the bottom. 

A heater doesn’t come as standard, but there are two discrete ports at the base of the tank — an inflow and outflow — that you can connect up to whatever you like. If you want to plump for your own filtration, connect something up and away you go. Get a pump and an inline heater and you can go full blown tropical. Splash out on a chiller, and you can keep some delicate species happy. 

At 23 l capacity (including the outer ring), you should choose jellies to fit. The usual Moon jellies will soon overgrow, while the lighting — as pretty as it is — isn’t likely to sustain the demanding photosynthetic species. To be fair, it’s not exactly feasible to be cruel to a jellyfish in any traditional sense, so even if you did just stick whatever species in and it didn’t fare too well, the only thing that would suffer would be your bank account. 

But where on earth do you get jellies from in the first place? It’s not exactly something you see in your everyday aquatic store. As luck has it, more and more retailers are taking the plunge, and Cubic can direct you to any local to you. Or you can just get online. Stores like specialise in selling squishy spineless lumps. 


Look about your room right now. Is there anywhere that a lava lamp would look cool? If there is, then one of these would look a total treat there. 

You get a fair bit for your money, and insofar as it’s possible with jellyfish, the set-up is pretty ‘hands off’. Construction is sturdy enough for peace of mind, and unlike glass tanks, you’ll struggle to break this in a topple. 

Even non-fishkeepers will be all over this — plenty of them have already been sniffing around my sample model in the office. 

Ease of use: 4/5
Features: 4/5
Value for money: 4/5
Overall 4/5
Price: Cubic Orbit 20 £249.99, extra trim rings £24.99.
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