Hello there! Welcome to BD.org
Congrats on the new beardie!
Best schedule for the supplements are as follows:
Calcium w/D3 dusted on the food 5 days a week, one feeding.
Multi-vitamins dusted on the food 2 days a week, one feeding.
The best brands for both are Rep-Cal, you can see them here:
http://www.petmountain.com/search/417/50/1/1/?Order=11&Color=&Filter=
Lighting is very important so what might be best for you is to get a ReptiSun 10.0 bulb for your UVB.
http://www.petmountain.com/product/fluorescent/504983/zoo-med-reptisun-10.0-uvb-bulb.html
Get the tube bulb and NOT the compact as they aren't good for your beardie at all. You will need a different fixture for the ReptiSun, you can either get the standard tube type fixtures that go on top of aquariums or pick up one at HomeDepot or some hardware store.
The basking bulbs are fine, any standard household bulb works great and provides nice white light. I'm not sure what fixture you're using (that t-5 fixture) but if the household bulbs fit in that, that's great and you could still use it for that.
I believe people have said the "reptile" type halogen lights put out more heat than standard household bulbs, but they're more expensive.
What you want is a good source of UVB for your beardie and bright white light in combination. If you have a
UVB bulb and basking bulb next to each other, your beardie can get both at the same time and that's excellent for them.
Lights should be on between 12-14 hours a day. The basking bulbs are to get the temperature to about 100-110 in the basking area.
The 20 long is kind of a small tank for a 20" beardie, you really should think about getting something larger as soon as you can. I know it's not easy to get everything right from the start but just keep that in mind.
It would be helpful if you could answer some of these questions so we could all help with anything else you might need.
How old is your dragon?
How long have you had your dragon?
How long is your dragon?
What is the sex of your dragon?
What size enclosure do you have your dragon in?
What type substrate do you have on the bottom of your tank?
Do you use UVB lights?
If so, Is it a coil, compact, fluorescent tube, or Mercury Vapor bulb?
What is the brand name and number of your bulb? Wattage (if MVB)?
How old is your
UVB bulb?
How close can your dragon get to the UVB?
Do you use a separate basking bulb? What kind and what is the wattage?
What are the basking temps?
What is the cool side temp?
Do you take the temps with a stick on thermometer, a digital thermometer with a wire and a probe end or a temp gun?
Where exactly are you taking your basking temps?
Do you use a heat rock or heat pad?
What do you feed your dragon? Please be specific.
How often do you feed and what time do you feed (morning, afternoon, night)?
Do you gutload (feed) your crickets, worms, etc?
Do you use vitamin or calcium supplements? What brand(s)? How many days a week do you use each of them?
Is your dragon having regular bowel movements (poops)?
Do you
bath your dragon? How often?
Do you mist your dragon or offer water other than in the
bath?
Does your dragon share an enclosure with another dragon?
Have you gotten a vet check and fecal done?