The minimum size enclosure for up to 2 adult dragons should be 48" x 24" x 24". A basking site should be provided under the hot spot and the UV lighting, plus an area to hide in and a good sized branch angled up into the cool end for thermoregulation. Bearded Dragons need to bask and they need high temperatures to help with the digestive process. Basking area should be about 100 degrees Fahrenheit with an ambient temperature of 75F and then dropping to about 65F at nighttime (a good rule of thumb - if you are comfortable then your dragon is).
When setting up the tank/enclosure, gear the heating and lighting to operate on a day/night cycle - this can be done fairly easily using timers and thermostats. It will also help if you can adjust the temperature say monthly in line with seasonal changes - you are after all setting up a microclimate.

Lighting - UVA/UVB Requirements

Along with all the other things to consider when setting up for your reptile there is the matter of lighting & heating. No matter whom you talk to (nor which expert you check with on-line or otherwise) you end up confused by the choice available.

This section is not meant to be an advisory fact sheet but more a 'save some of the searching' help sheet so please read, check out the links etc. then make your decision.

In general reptiles need light, which includes UVA/UVB in varying amounts, this may be provided by using a combination of neon tube, mercury vapour, spot-lights (incandescent) and dichroic lighting. All except the spots will provide the UVA/UVB in varying amounts/useable levels, at assorted distances and depending on the method used the actual area on the ground will vary (neons over the length of the tube, others dependant on the light thrown). A visit to www.uvguide.co.uk provides good general info on the various types of lighting, distribution of usable UVA/UVB and a survey of currently available systems including levels of UVA/UVB at varying distances from the light source. A number of government Occupational Health & Safety sites have commentaries in regard to quartz halogen (dichroic) & mercury vapour lights (see prompts on uv guide site) which when read tend to indicate that being within distances of less than 30cm is equivalent (minute for minute), to sitting in the midday sun without an SPF 30 sunscreen.
Reptilesdownunder had a survey conducted in South Australia on the commercially available systems generally recommended for reptiles - see www.reptilesdownunder.com/reptile/enclosure/uvlighting.php

At this point you should be totally confused - so back to basics, ask yourself these
questions: -

1/. How far is the basking area from the light source?
2/. How much can you afford?
3/. How often do you want to replace the lighting system (see also 2/.)?
4/. Will the lighting source also provide the main heating?

I.e. Close to the light source, not providing heating, replace regularly then Neon tubes are a choice.
A fair distance from the source, providing heating, 3000+ hours between replacement then consider Mercury vapour.

Having said all that you may also consider Dichroic lighting as an alternative to either system - whilst there is little in the way of official surveys on this there are also a number of people out there already using this system, as a search of the internet shows.

Heating Set-Up (Assume a 48in. Tank)

A simple way to effect this is to provide a heat-pad under the tank controlled by a light dimmer (the dimmer can be used to reduce background heat especially toward winter for brumation purposes) - this will provide a background/nighttime heat - plus 2x 60watt incandescent spots focused on the basking spot - these should provide the additional heat required during the day. I run these plus the UVA/UVB light though a timer to provide 8 to 14 hours daylight depending on time of year. You can also run a ceramic heating bulb on a thermostat set to kick in at under say 65F
To monitor the setup one thermometer on the back wall at the cool end to show lower temp and a probe thermometer near/on the basking spot are all you need.
Hot rocks should not be considered as they are can cause belly burns, as dragons are not very sensitive to extreme heat through the belly.

Substrate

This is the material covering the bottom of the tank and is probably the most disputed area of Lizard Husbandry and you should research this yourself before making any decision. I use slate tiles under the eating bowls (easy to clean & disinfect) sandstone over half the balance of the floor (helps keep claws short without trimming) and bull dust (our fine red desert sand - sorry you can't get it) for effect. Don't use crushed walnut shell or other sharp bases these can be swallowed when hunting crickets and either lacerate the gut or cause impaction. Good quality Astroturf can also be used but make sure that there are NO loose threads that can be picked at and eaten by a bored dragon. Butchers paper is ideal but not exactly pleasing on the eye.

Feeding

Frequency of feeding gets discussed a bit but rule of thumb for adults - offer veggies/fruit/flowers daily. Provide live food every 3rd or 4th day and as much as they will eat in 5 minutes. If you have one behaving like a teenage boy (refusing veggies) hold off on the livestock for another day or two - this usually works, although mine likes to be hand fed on his sleeping branch!
Babies need a constant supply of fine chopped veggies plus very small crickets a couple of times a day.
In all cases leave enough time for digestion before lights out at night i.e. don't feed live after around 3~4 pm.

Bearded Dragons like fruit and vegetables as well as meat. They like a large variety of live insects, which include black and brown crickets, locusts, cockroaches, mealworms and wax worms, both mealworms and wax worms can be fattening and should not be used as a staple food (imagine a kid in a sweet shop). A good measure for the size of live insects to feed is that their length should not exceed the distance between the eyes on your dragon's head - having said that I've a 50cm male who can knock off a 6cm locust in a bite. Do not feed mealworms to baby dragons as they contain chitin which is hard to digest. Do not feed them insects from your garden, as you do not know if they have been sprayed with anything that can be harmful to your dragon this also goes for plant life. Fresh fruit and vegetables must be offered daily remembering that they like variety. Vegetables must always be washed before feeding to your dragon. They like to eat Chicory, Watercress, Broccoli, Courgettes, Carrot, Peas, Butternut (sweet) pumpkin Apple, Banana (as a treat- not good for them in quantity), Kiwi, Mango, Melon and grapes, dandelion flowers, day lily and hibiscus petals are happily accepted - orange is a colour they seem to like in the food. Avoid spinach and kale as they are calcium binders and affect the dragon's bones. Another thing to avoid is iceberg lettuce, as this has no nutritional value to the dragon. Make sure to chop the food into small bite size pieces to avoid choking.

Bearded dragons require supplemental calcium and vitamin D3. This should be provided by dusting the live food at least once a week with supplements such as reptical or Nutrobal (with babies this should be done daily to aid strong bone formation) the UVA/UVB then assists in the proper absorption of the minerals. Water should be offered in a shallow dish but sufficient moisture is usually obtained from the vegetables. Your dragon may like a weekly spray as a treat but this is not essential.
Drinking dew from plants gets mentioned on a number of sites - you don't get much dew after your third week of 85F+ temperatures and very low humidity levels!

Brumation

This is natural and a cool-down period is needed for successful breeding. There are dragons that are happy to stay up all year but generally they will slow down towards winter. My practice (based on general Australian experience) is to reduce temperatures over 4~6 weeks in autumn. Your dragon will already have slowed down eating and extended his sleeping periods naturally. Check that he's had a good clear out of his bowel at the end of the 6 weeks as anything left in the gut can ferment/rot etc., turn off the last heating/lighting and put him in a cool place for the next 3 months. At this point he will start to stir again, so reverse the process being ready for an eating binge. They don't lose weight (mine lost around 5grams only) but they wake up really hungry. I have a couple of large shoe boxes with a flap in the front floored with paper kitty litter pellets as insulation, these are put into a small tank in an unheated spare room. Water is provided as this is not full hibernation and occasionally on a good day one will get up for a short wander then back to bed DO NOT FEED AT THIS TIME as they will not be able to digest it.

Hygiene

As with all animals basic hygiene rules should be followed, more so with dragons as they carry a version of salmonella. They can also carry coccidea and intestinal worms so you should have your vet check the droppings say 6 monthly to check this. When introducing a new dragon he should checked for worms & be quarantined for 2~3 weeks first, additionally hand washing after handling other dragons & before handling your own helps prevent the spread of disease.

General Information

Direct natural sunlight is very beneficial and should be provided if possible. However bearded dragons should never be placed outside in a glass enclosure. The animal could easily overheat and die. When outside provide an area of shade and water (this probably will not be used but should be there anyway).

Bearded Dragons live for an average of 4-10 years depending on their quality of life (your attention to detail), if they have had good lighting and temperatures maintained as well as a good balanced diet then you could expect your dragon to live longer than a dragon that hasn't. But if you have a female that has been repeatedly bred then her life span can be expected to be quite short.

Beardies will keep you amused for a long time. Just observing and interacting with them is fascinating. There are 2 things that the Beardie does; one is to nod its head - fast nod dominance, slow nod OK I see you and the other is the arm waving (this is a sign of submissive behaviour -more like Hi, I'm here, I'm a friend). When they sit with open mouths this is their way of cooling down their body temperature.
It is not advisable to keep two males together as they will probably fight; more so if a female is present. If you would like to keep more than one Beardie then make sure that there is only one male in the enclosure, and if one starts to show aggression (rather than mating behaviour) then separate them - it won't get better and you could easily end up with one dragon plus a do-it-yourself kit for your vet to repair. (It's really important to find a good vet who knows about reptiles)
Do not mix other reptiles with Bearded Dragons, as it is an accident/fatality waiting to happen.

Links

Melissa Kaplan at www.anapsid.org has one of the most informative sites available and should be a must for everyone.

This care sheet is based on my own personal experiences with Dragons, the original care sheet from the ReptileKeeper's site and discussions on the forum site Australianreptilesonline and should be used as a guide only. When in doubt refer to a qualified vet (or maybe your local zoo).

If all this is too much for you please reconsider taking on a dragon, as it is not fair to either one of you.