Congratulations on deciding to get a beardie, you will not be disspointed, for those who can put the effort time and money into them they are truly rewarding creatures to care for!
As far as temps, and measuring the temps goes, its all really quite simple. You need a basking spot of around 100-110degrees, and an overall cage temp in the mid to high 80s, with a cool spot in the high 70s to low 80s. You should measure the temps with ONLY a temp gun (www.proexotics.com) or a indoor/outdoor digital thermometer (available for about 5$ at walmart or home depot). The digital thermometers have a probe that you can place anywhere in the cage for an acurate reading. The stick on thermometers you buy at petstores are a waste of money. They tend to be very inacurate (I had one that was reading 15degrees too low!) Plus, many of them only measure temps up to 100degrees.
For substrate, sand is not the best option. It is not an option AT ALL for babies under one year of age or 12inches in length. For adults it is an option, but it is still pretty hazardous. Sand is generally frowned upon because it can cause impactons (build ups in the intestines that eventually cause partial or complete blockage) that can be life threatening. Sometimes impactions result in surgeries to remove the clump that is stuck. Sand is also messy (sticks to the veggies and bugs you are feeding) and harbors bacteria. Because it is particulate it is almost impossible to keep clean of bacteria. If you use sand a complete substrate change is needed once a week or every other week. There are TONS of alternatives to sand, the easiest and cheapest is paper towels (Diva brand paper towels have worked best for me because they are thicker than others). You can also use newspaper, linelium, indoor/outdoor carpetting, tile, or non-adhesive shelf liner. All substrates have their pros and cons, in the end it really comes down to which works best for you. Non adhesive shelf liner or linelium are the easiest to clean.
One note...if you do decide to use sand when your beardie is an adult, never use the sand from the petstore. Anything that is labeled Calci-sand, viti-sand, or claims to be digestable is very very very dangerous. Use only fine grain sifted, washed play sand from homedepot.
Good luck with your new beardie! Do lots of research and make sure you are fully ready for the little guy before you get him
Ask lots of questions! This forum is a great place to find info, you can also browse back through the old threads and read them (which is very informative).
check out www.beautifuldragons.com for an AWESOME beardie webpage complete with care sheets and TONS of tips and info!

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