I hope you got your setup worked out, he doesn't look too bad but there are 2 MAJOR ISSUES you have that need corrected, your
UVB light and your temperatures. Once these are worked out he should be fine.
Obviously you know that a Reptisun 5.0 is not nearly adequate, they are for tropical reptiles, not desert. And you obviously want a long, fluorescent tube light and fixture, not the compact (regular lightbulb shape) or coiled Reptisun. So you can buy a cheap fixture for the 18" inch Reptisun 10.0 T8 UVB tube at Walmart for $10. If you're going to buy the Reptisun 10.0 T5 High-Output UVB tube you'll need to buy the Reptisun tube fixture/hood the same length as the bulb you get, or order a generic one on Amazon for less money, that will work for the T5 High-Output tube. The T5 High-Output UVB tube puts out 25 watts and the T8 is I believe 17 watts, so that is the difference in fixtures. Finding an 18" or 24" T5 rated fixture in a store is tough, maybe Lowes or Home Depot, but I doubt it. The beauty of the 10.0 T5 High-Output Reptisun UVB tube vs. the T8 is that the T5 can sit on top of a mesh lid (not glass, no UVB can penetrate glass) as long as the T5 is within 8" of the basking spot. If you mount the T5 inside the tank so that there is nothing between the T5 tube and the basking spot then it can be 11" away from the basking spot. If you buy the T8 10.0 tube then you absolutely must mount the tube inside his tank with no mesh lid in-between the tube and the basking spot. The T8 will not penetrate a mesh lid at any distance. So in this case you need to get some 3M Command Hooks or Industrial Strength 3M Velcro rated at least for 10 pounds (I use the thicker, Industrial 3M Velcro rectangular pieces rated at 16 pounds, a pack of 2 long pieceses cost me $6 at Walmart). The T8 UVB tube must be mounted within 8" inches of the basking spot at the farthest, with nothing in-between the tube and your beardie.
You should mount the UVB tube right alongside the basking light so that your beardie gets both while basking on his basking spot. The basking light can be set on top of a mesh lid and can be at any height or distance from your beardie as long as your temperatures are correct, which they are not. So here's your second major issue.
Please remove the divider you put in your 30 gallon tank. It is a large enough tank for you to get a proper temperature gradient for your beardie, and the reason he wasn't eating wasn't because the tank was too large for him, it was because your temperatures were way off.
***** I think you said you have either a temperature gun or a digital thermometer with a probe on a wire? If so good, if not you need to go spend $10 and get one at Petco or PetSmart ASAP, because those round thermometers are awful, and usually off by 20 degrees in either direction. So not only could you be cooking your beardie, there is no way to measure the temperature of your basking spot without a probe or a gun.
*****YOU SHOULD HAVE 3 DISTINCT TEMPERATURE ZONES INSIDE HIS TANK!!!! THIS IS WHY YOU NEED TO REMOVE THE DIVIDER YOU PUT IN HIS TANK, BECAUSE YOU CANNOT GET A PROPER TEMPERATURE GRADIENT IN A TANK SMALLER THAN AT THE VERY LEAST A 20 GALLON LONG. YOUR 30 GALLON WILL ALLOW FOR A PERFECT TEMPERATURE GRADIENT IF YOU REMOVE THE DIVIDER! So you need 3 distinct temperature zones:
COOL SIDE: (opposite the side with his basking spot)-75-80 degrees Fahrenheit
HOT SIDE: (side that contains and is around basking spot)-88-93 degrees Fahrenheit
****BASKING SPOT: For a baby or juvenile should be between 105-110 degrees Fahrenheit, NO HOTTER! 115 DEGREES AS LISTED ABOVE IS TOO HOT!!! 110 DEGREES MAXIMUM!!!
-Adults at a year or older like their basking spot a bit cooler, between 100-105 degrees Fahrenheit....
****VERY IMPORTANT!!!*** IF YOU'RE USING A DIGITAL THERMOMETER WITH A PROBE, YOU MUST PLACE THE PROBE IN THE AREA YOU WANT TO MEASURE AND THEN ALLOW THE PROBE TO SIT THERE FOR AT LEAST 20-30 MINUTES BEFORE YOU READ THE TEMPERATURE, OTHERWISE THE TEMPERATURES COULD ACTUALLY BE 10+ DEGREES HOTTER THAN YOU READ!!!****
So once you mount your Reptisun 10.0 UVB tube either inside the tank if a T8 or either inside the tank or on top of the mesh lid if a T5 tube, the first thing you must make sure is that the UVB tube is at a proper distance from the basking spot, as I listed above depending on what UVB tube you buy. After you get the UVB tube at the correct distance from the UVB tube, ***DO NOT MOVE EITHER THE UVB TUBE OR THE BASKING SPOT AGAIN!!! AT THIS POINT YOU WILL ONLY ADJUST THE HEIGHT AND/OR WATTAGE OF YOUR BASKING BULB TO GET THE CORRECT TEMPERATURES IN YOUR 3 ZONES, BECAUSE THE DISTANCE OF THE BASKING BULB FROM THE BASKING SPOT DOESN'T MATTER!***So after you get your UVB tube mounted, and your basking platform/log/rock at the correct distance from your UVB tube, now it's time to set up your basking bulb, or bulbs if necessary, and get your 3 important temperature zones correct. Start with getting your basking spot temperature correct, which should be between 105-110 degrees Fahrenheit. YOU DO NOT NEED TO BUY EXPENSIVE BASKING BULBS MADE FOR REPTILES AT A PET STORE!!! ALL YOU NEED IS A REGULAR, HOUSEHOLD HALOGEN LIGHTBULB! IT MUST BE BRIGHT WHITE, NOT FROSTED WHITE! I use halogen indoor flood bulbs, they work great, and that way you're only spending a couple dollars a bulb, so you can buy a couple of different wattages to try to get the temps correct, and you're not spending a fortune. For a 30 gallon tank I would start with a main basking bulb of 100 watts. Put a normal, halogen bulb in your basking bulb fixture, and place this fixture overtop of the basking spot/platform/rock/log, and make sure it's also right next to the UVB tube so that he will get both lights at the same time while basking. Start here. Take the gun and aim it directly at the spot where your beardie will be sitting while basking and take the temperature, or if using a probe thermometer then place the probe exactly on the spot where your beardie will be sitting to bask, AND LET THE PROBE SIT ON THE BASKING SPOT FOR 20 MINUTES AT LEAST!!! After 20-30 minutes of having the probe sitting in the basking spot read the temperature. You want it between 105-110 degrees Fahrenheit, not one degree hotter!!! If the temperature is between 105-110 that's great, if it's higher you can do one of two things, depending on how much higher it is. You can either try a different wattage of bulb (75 watt or 90 watt are typically your options for regular lightbulbs), or you can raise your basking light up. YOU MAY WANT TO INVEST $15 AT PETCO OR PETSMART IN A HEIGHT-ADJUSTABLE BRACKET FOR YOUR BASKING FIXTURE!!! They both sell them, they look like an L-shaped bracket that the light fixture hangs from and the bracket mounts to your tank. This makes it very easy to get your basking spot temperature correct very quickly.
Once you get your basking spot temperature between 105-110, next you want to either use your temperature gun to take the temperature of your HOT SIDE, or you want to move the probe of your thermometer off of the basking spot and down to the bottom of your tank, on the ground, next to the bottom of whatever your basking platform is. Allow the probe to sit there again for 20-30 minutes, then read the temperature, which should be between 88-93 degrees. If both your basking spot and your hot side temperatures are too huge, I suggest a lower wattage bulb. Again you'll need to either change the wattage of the bulb or play with the height of the basking bulb to get the hot side between 88-93 degrees.
Once you have your basking spot and Hot Side temperatures correct, you need to measure the temperature of your Cold Side, which is on the opposite side of the tank. Put your thermometer probe on the floor of the tank on the side opposite of the Hot Side and allow the probe to sit there for 20-30 minutes before reading the temperature. DO NOT MEASURE THE COLD SIDE TEMPERATURE INSIDE ANY CAVES OR UNDER ANY DECOR OR HIDES!!! You want to get a Cool Side temperature reading that is out in the open, in whatever light the basking bulb is putting off. YOU WANT YOUR COOL SIDE TEMPERATURE TO BE BETWEEN 75-80 DEGREES!!! This is extremely important because if your beardie has no place to go when he gets too hot and wants to cool down, typically they will stop eating, become dehydrated, and sometimes glass surf and dig. Other times, if it's way above 75-80 degrees they just collapse and lay there with their eyes closed and don't move. With a 30 gallon tank you shouldn't need to add another basking bulb on the cool side to get the temperature up to 75 degrees, the one basking bulb over the basking spot should do it. If the cool side is hotter than 80 degrees then you again need to play with moving the basking light up, or using a lower wattage....
Having these 3 temperatures correct is as vital to your beardie's life as the 10.0 UVB tube is. If his temperatures are too cold he cannot digest his food, if the temperatures are too high you'll dehydrate him and basically slowly cook him.
Your beardie should get 12-14 hours of both lights every single day!!!
****NO NIGHTTIME LIGHTS AT ALL!!! Beardies see in color just like us, so any light on at night will disrupt their sleep. You want their temperatures at nighttime to drop, just like they do in the wild, so your beardie will sleep comfortably. Most people need no heat source at night at all. MEASURE THE TEMPERATURE OF HIS COOL SIDE ONCE HIS LIGHTS HAVE BEEN OFF FOR A GOOD 2-3 HOURS. IF THE TEMPERATURE IS AT LEAST 65 DEGREES, THEN YOU NEED NO NIGHTTIME HEAT SOURCE AT ALL. Most people keep their house at least 65 degrees at night, so the cool side temperature will typically measure at least 65 degrees, usually higher, and you need no nighttime heat at all. IF FOR SOME REASON YOUR HOUSE OR THE ROOM YOU KEEP HIS TANK IN IS REALLY COLD AND THE COOL SIDE TEMPERATURE MEASURES BELOW 65 DEGREES, THEN YOU WANT TO ADD A LOW WATTAGE CERAMIC HEAT EMITTER (CHE) AND MOUNT IT OVER TOP OF THE COOL SIDE, AND TURN IT ON AT NIGHTTIME ONLY!!! As I already stated, you most likely will not need any additional nighttime heat source. And once again, Beardies like a much cooler nighttime temperature, just like the desert at night, so as long as his cool side is at least 65 degrees you're good to go.