Most reptiles when kept in captivity will require some level of specialised lighting, when setting up your Bearded Dragon vivarium this is no different.
There are a wide range of reptile lighting products out there and choosing the right ones can be confusing. Hopefully the following information will help you out but the quick answer is: Get a fluorescent strip light with 10-12% UVB and a heat bulb with UVA and full light spectrum to create a basking spot of 110F / 45C.
For Bearded Dragons you need two different types of lights, a basking light to simulate the suns heat and a fluorescent light to provide the necessary UV radiation to help the dragon metabolise calcium and other essential vitamins properly, which is no different to us humans.
UVA, UVB, UVC radiation
The sun emits ultraviolet (UV) radiation which you’ll probably know about as this is what causes skin tans, skin cancer and so on. But it’s actually the different wavelengths or types of UV radiation that cause these effects.Your dragon requires a source of UVA and UVB.
UVA is generally harmless and has few known benefits to us humans, although excessive quantities can damage vitamin A production. In reptiles however UVA encourages natural behaviour such as breeding and basking. Lizards are very sensitive to it and also use it in part to identify food and mates. Bearded Dragons have a special scale on top of their head that’s thought to be linked to this, more specifically it’s linked to the Pineal Gland which in most reptiles is always close to the brain.
UVB radiation is what bearded dragons simply must have, failure to provide a source of this is to condemn your dragon to a slow agonising death. UVB provides a way for the reptile (and us Humans) to create vitamin D in their skin – specifically vitamin D3 which is also used to metabolise calcium in the dragon which encourages healthy growth, without this then they would have dietary problems leading to issues such as metabolic bone disease. Too much UVB is a bad thing and can cause DNA damage and problems with vitamin A production.
UVC is harmful and you don’t want to be providing a source of this to anything living (unless you slowly want to kill it), it’s this type of UV radiation that causes the most damage to living cells and also what creates the ozone layer and our atmosphere blocks out the most of. It’s mutagenic and carcinogenic. Bad for everything living.
Choosing the right lighting for your Bearded Dragon
So how do you choose the right bulb? They all have different levels, 3% to 12% UVB, some with ‘vitamin D3 added’, some bulbs provide UVA, some have different colour lights. There are different types as well such as incandescent, halogen and fluorescent.
To make the choice easy, just think for a second about the Bearded Dragon habitat in the wild. The Pogona Vitticeps (The common Bearded Dragon in the pet shops) lives out in the very hot semi-desert areas of Australia, it’s always out in the sun basking. That means it obviously needs a fair amount of sun light and the associated ultraviolet that is present in the sun light as well as the heat generated.
So you need a heat lamp and a relatively high source of UVA and UVB, the below should help you out.
Choosing a heat lamp for your vivarium
This depends on two things, the area of the terrarium and it’s height, or rather how far away the heat lamp will be mounted. I once went into one reptile shop and asked about which light to use and what would be right giving them the dimensions etc… of my setup and the shop owner told me to take any one and ‘suck it and see’. I’ve not been back there since! On any light bulb for a reptile the packaging will have some level of rating on the side and the lux and heat given off at set distances from the bulb.
For Bearded Dragons you want a bulb that will give you 110F / 45C for the hot end, it can be higher as the Agamid family of lizards senses heat from above them so they’ll move out if too hot. However you need to ensure that the other end of the vivarium is at about 80F / 27C for them to cool down in. You can control this by the decor/ furnishings in the terrarium and how you place the light in the vivarium, using a reflector to help reduce the area heated by the lamp (also reflecting all heat and light downwards).
A lot of bulbs now have specific reflectors in them to provide a tight cone of light which also helps. Avoid placing this on the side of the terrarium as the dragons (especially the young) will climb on this. Avoid also adding a cage over the light as, again, they’ll climb on it and either way they end up with burns. Instead mount it from the ceiling of your setup.
Bearded Dragons regulate their body temperature by moving between different temperate zones such as basking in the sun to hiding in the shade – they even gape (open their mouth) to let heat out. Because of the way they sense heat this is why you should never, ever, under any circumstances use anything that provides heat from underneath the beardie such as a heat rock or heat mat as they can’t tell how hot it is and will burn themselves.
You can use ordinary incandescent household bulbs and these will work fine and are much cheaper, however, the reptile bulbs have better light spectrum’s for the lizards. They’re also a much better source of UVA radiation which promotes natural healthy behaviour connected with their Pineal Gland (that weird scale on top of their heads!). Worth the price in my opinion.
You want a bulb that produces the full spectrum of light, so not infrared, green, blue etc… something that does all spectrums and wavelengths since that replicates the sun.
In the minimum 4ft x 2ft x 2ft vivarium size, a 75 Watt bulb should be hot enough, if the vivarium is already in your house. The substrate will also carry and distribute much of the heat. In a 2ft x2ft x2ft tank a 60 Watt bulb should be enough, anything smaller will be a 40 Watt bulb or there abouts. That should give you a basking spot of around 110-120F. An energy saving bulb won’t provide much heat at all before you think about using one to save money on your electricity bills!
If you have the cash you can also invest in a thermostat to precisely control the heat, although it’s not really necessary for Bearded Dragons since they come from a hot place anyway and I’ve not really ever needed one other than for incubating Bearded Dragon eggs. However, I have one exception, if like me you have several vivariums stacked one on top of the other then you’ll want a thermostat for at least the top vivarium since the heat from the ones beneath it will rise up and give additional heat.
It’s also recommended to get a small thermometer to measure the heat range in the vivarium to ensure it’s correctly set up.
Choosing a UVB light for your vivarium
Bearded Dragons need UVB, plain and simple! Your best bet is to get a strip bulb (fluorescent), get it for as big as you can fit inside the tank. Mount it on the ceiling with a reflector behind it to make sure as much of the UVB is directed down to the floor – Arcadia sell some great reflectors for this.
The beardie like other lizards also regulates their exposure to UVB so in the vivarium provide different perches and places to hide under, they’ll climb up when they want more UV and hide under the logs, plants etc… to avoid the UV and the heat, a good amount of substrate will also allow them to dig a burrow to hide in as well.
All UVB bulbs have different levels of UVB radiation, for Bearded Dragons you want the highest possible which is 12% from Arcadia or 10% from Exo Terra. I’ve used both and generally found them to be fine, although the Arcadia seem to last a bit longer and I’ve found them to be a bit cheaper as well – they also claim to be enhanced with vitamin D3, which I think is just a marketing ploy since the UV light promotes synthesis of vitamin D3 in the skin, unless there’s a specific wavelength of UVB that they’ve enhanced somehow.
There are less concerns over UVB bulbs as opposed to heat lamps, although the UVB bulb will get hot in the tank it’s not the biggest concern providing it’s emitting UVB. However, to use these strip lights you need a specific controller/ power supply which will provide the correct wattage for the bulb.
So far I’ve found the Exo Terra controllers to be the best as you can run 2 vivariums from them, they don’t need any starter switches, you can run any size UVB light from them and they don’t make the bulbs flicker. The heat emitted from this controller is substantially less than that of the Arcadia ones (or other brands for that matter).
The other issue with UVB lights is that over time the amount of UVB radiation generated decreases and without a rather expensive sensor to detect the UV levels you have no way of knowing when to replace the bulbs. They’ll still be working and giving off light, just not the UVB radiation you need.
The rule of thumb is typically replace these UVB bulbs once every 12 months, if you’ve not changed your bulb in a while and your dragon is looking sluggish and lethargic, try swapping out the bulb for a new one and see if that improves. The packaging for the UVB bulb will state how often to change and the effective distance e.g. effective up to 20 inches. That means if your UVB bulb is closer to the floor then you can potentially use a lower percentage bulb.