Building Vivaria

Kevin Du Rose
July 1998
Last update: 17 February 2000

In August 1995 I started the wonderful hobby of keeping Dendrobates. I planned a large(-ish) vivarium which measured approximately 1.5m x 0.5m x 0.75m high. As I am writing this article, the pair of D. azureus that inhabit my vivarium are spawning. During the last year, they have produced about 250 eggs. The vivarium also contains a small colony of D. ventrimaculatus that have also produced about 75 froglets - although I am currently attempting to replace these with some captive bred D. pumilio.

Lighting
This is generally 2 x 42-inch fluorescent tubes. Three would be better, but would be expensive. The best fluorescent tube to use is a Hagen Lifeglow. This tube is twice as bright as any other tube, has an internal reflector and emits UV. It is especially recommended for reptiles. I mounted these tubes inside my viv. When constructing a vivarium, remember to make the tank about 2 inches longer than the size of the tubes you intend to use, bearing in mind a large tube is only slightly more expensive than a small one. The wires can be run out of the back of the vivarium. I use Bluetac to seal round the wire so that the fruit flies stay inside!

Filtration
I used an Aquaclear 402 (1160 l.p.h) fitted with a cartridge circulating water to the opposite side of the vivarium. This then runs down a large piece of bogwood that is heavily cracked and so has a massive surface area. This enables the colonisation of friendly bacteria after only a few months. Together with the plants this should remove any waste products from the system.

Heating and Ventilation
I simply use a standard aquarium heater. I don’t use a heat-pad because I have lost too many frogs in the past. Trial and error will be needed to get the temperature correct.

I set the heater at 85°F, and is on virtually all of the time. It switches off only in really hot weather. As a precaution, I switch it off in heat waves and switch one of the fluorescent tubes off as well. It may be interesting to note that the lower reaches of the vivarium are usually at about 70°F and the upper reaches about 80°F. Additional heating in the vivarium obviously comes from the lighting. It is worth remembering that in nature a frog will automatically move its situation to suit the temperature. In the vivarium, however, this would be difficult for it to do in some situations.

When I first set up my vivarium, as I had expected condensation obscured the front glass, which affected visibility of the frogs. A small computer fan stood in such a way that it blew over the ventilation holes of the tank easily solved this. However, it did not blow directly down, as this would have caused a whirlwind, to the detriment of the frogs’ well-being. In my experience, it is best to set the fan on a time switch to conserve heat and also to conserve water - excessive evaporation is a problem. About 10 x 15 minute bursts over 24 hours has proved successful in my case. You can always over-ride this on the time switch if needs be.

Furnishing
A small pond area can be created to house the heater and power head. I would recommend as a substrate the use of ‘Litag’. This is used in pond filters and is available from pond and aquatic centres. It consists of clay balls and is about half the weight of gravel, is cheaper, fairly smooth and does not float like the clay balls sometimes used for potting plants. This can then be covered with a layer of Beech leaves, while the back wall and sides of my vivarium are covered with 4mm thick cork tiles. I would try to use thicker tiles if possible, though.

Recently I have covered the back of a couple of vivaria with bark from giant Cedar trees. It can be pulled away with your fingers in big chunks but does not harm the tree. The consistency is that of polystyrene and can easily be worked with a saw or bread knife and coarse sandpaper. I have read that bark can leach toxins, but I have encountered no problems in this direction. My frogs live under pieces of it. Another advantage is that if soft water is used, spores of mosses and ferns lying dormant on its surface will begin to grow.

My vivarium has several pieces of bogwood placed along the back wall, where various bromeliads have been put. I would recommend Neoregelia ampullacea and Neoregelia tigrina for the upper reaches of the vivarium. For those lower parts of the display I would suggest both Neoregelia meyendorfii and Guzmania lingulata.

N. ampullacea and its cousins have a stoloniferous habit i.e. they grow by extending offshoots in a creeping habit, like buttercups. In order to propagate them, I simply drill a 5mm-diameter hole into bogwood or punch a hole into Cedar bark or peat block. This hole forms the perfect place to push a cutting of the plant complete with part of the stolon. Rooting normally takes around two weeks.

I also grow Ficus pumila, which covers the back wall. The problem with this plant is that it is very invasive, and has to be cut back about once a month. Philodendron species also tend to take over, so these, too, need regular pruning.

Wet areas have been planted with Java moss Vesicularia dubyana. This moss grows faster and larger when grown terrestrially as opposed to aquatically. It will grow well on waterfalls especially over wood. If the vivarium is situated in a cold room and the walls are badly insulated, condensation will form and the moss will be able to grow up the walls of the vivarium. A smudge of clay may help the moss to gain a foothold, and also to retain moisture.

So.... that is the basic set-up. I would very much like to hear from anyone with any other system that has worked for them. Just a thought: How do you feel at the moment, if you’re reading this and the sun is shining. I bet you feel great! But if it’s January and it’s hardly got light for days, I bet you feel a bit down. So, spare a thought for your frogs. It must be depressing for them living in the corner of a shed, dimly lit by an ancient fluorescent tube. No wonder they haven’t spawned for ages, if at all.