Rio Reptiles
Rio Reptiles - A Rescue Resort



My Take on Lighting Setups

What bulbs should I use? Which setup is better? What's the difference?

One of the first things people find out about housing a bearded dragon is that it needs a special lighting setup to keep it happy and healthy. From there it can become some what confusing and sometimes difficult. Most of the time it depends on preference or recommendations, but in my opinion they both have their places.

First you should understand how the different bulbs work in relation to the dragons basking habits. The theory behind the linear flourescent uvb lamps is what they call the shade method. The shade method requires you to make the entire area of the dragons vivarium to that which resembles being outside in the shade on a sunny day. A considerable amout of uvb exposure is available as filtered sunlight without having to be exposed to it directly. If you were to check the amount of uvb available on a sunny day in the shade with a meter, you would be amazed at how much there is. Although there is no substitute for the real thing, the Reptisun 10 linear bulbs supply an acceptable amount of uvb when used properly.

The mercury vapor bulbs are meant to simulate a patch of direct sunlight by supplying a high amount of uvb in a smaller area, such as a small patch of direct sunlight would do. They also supply heat within that area which makes them perfect for active basking. With mercury vapor bulbs, exposure is good directly under the light during times of basking, but very little uvb is available away from it. Since their output of available uvb is supposed to be higher, a dragon should get an acceptable amount of uvb with shorter exposure times or while basking. The quality and output of these bulbs is under constant scrutiny and they should be researched prior to every purchase in order to avoid frequent manufacturing defects. Even the smallest change in specs on the materials used to make mercury vapors can seriously affect their output so make sure you're up to date with the latest test results.

Live long enough with lots of dragons and you start to see a pattern. Babies and juvies live for one thing... eat, bask, poop, grow! So for young dragons, I feel the merury vapor bulbs are more suited for their needs and their habits. You will rarely find a young dragon that is not basking, unless of course, the lights are off. As dragons grow into adults, it's almost a shock how much their eating and basking habits change, especially during brumation. Adult dragons no longer need to constantly eat to facilitate growth, so their protein intake is dramatically reduced and they only bask long enough to get the job done. They also spend more time lounging in the cooler temps, almost to regulate their own metabolism. This is where a fluorescent uvb bulb is the better choice for receiving constant exposure to a little uvb throughout the day. Most importantly, the linear bulb should be the longest size that will fit and run the full length of the enclosure for adequete exposure. This is how these bulbs are meant to be used and should not only cover a small area or part of the tank.

The fluorescent uvb's don't put out much heat and are not meant to be used for basking. So if you are using a fluorescent, or tube type uv bulb, a separate light is needed for heat. Bearded dragons, like all other reptiles, are ectotherms, and rely on the sun or other heat source to raise their body temps. The heat is what drives their metabolism and is used to facilitate digestion. For basking bulbs, any bright white light can be used that will raise the surface temps below it to the recommended range. Some people use household bulbs, but I like using spot like bulbs that concentrate the engergy into a smaller area. Depending on the distance, a 50 watt halogen will heat the surface below it more efficiently than a regular 75 watt incandescent. They cost a little more but save on electricity and wasted energy.

On the contrary, mercury vapors put out a lot of heat. I've had them fall out of their own threads they get so hot. For safety, it is important that a deep dome with a ceramic socket is used and plenty of ventilation is available. Because of this, they are great during winter or in cooler regions but can easily over heat too small of a tank. Money wise, they are a good value and can last a year before replacement is needed, twice as long as a fluorescent uvb which degrade within six months of use. Since they supply uvb and heat, only a single mercury vapor is needed most of the time. People who switch from fluorescents report increased appetite, better growth, and higher activity levels. For breeding or gravid female dragons, using mercury vapor bulbs can help them produce healthier clutches and rebound quickly.

So if I had to pick the better system, I would say both. If you start out using a mercury vapor bulb to raise your baby, I'm sure it will eat more and grow better. When it comes time to replace it, keep it for a basking bulb and add a linear fluorescent. Chances are ,your yearling dragon will stay somewhere between the basking area and cool side of the enclosure most of the time anyway. Also, remember to start using calcium powder with D3 at that time and you will be good to go.







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