This is a specific conversation about Bearded dragon lighting — UVB and basking done right — ask about yours and get one honest answer for your exact situation.
inparticular.ai
Bad lighting is the single most common husbandry mistake with bearded dragons — incorrect UVB output or wrong basking temperatures cause metabolic bone disease and chronic illness that many owners don't spot until real damage is done. You've had your dragon five years, so you clearly care, and sorting the lighting properly now absolutely matters. To point you at the best value bulb that'll actually last, I need a few quick details: what size is the enclosure, what bulbs are you using right now (brand and wattage if you know them), and roughly how old is your dragon?
He's five years old, in a 4x2x2 wooden vivarium. I've been using a ReptiGlo 10.0 compact bulb, the coiled type, 26 watt. I'm on a pension so I need something affordable, but I want it to last as long as possible so I'm not replacing it every few months.
inparticular.ai
Right, I'm glad you've mentioned the ReptiGlo compact — I need to be direct with you. Coiled compact UVB bulbs have a known problem: they produce uneven UV output and some wavelengths that can cause eye issues in bearded dragons over time. After five years your dragon has likely been UVB-deficient without either of you knowing it. For a 4x2x2 enclosure you really need a T5 HO linear tube running at least two thirds the length of the viv. Can I ask — do you currently have a T5 or T8 fluorescent fixture in the enclosure, or just the compact bulb fitting?
Just the compact fitting at the moment, nothing else. I didn't realise the coiled ones were a problem. I genuinely can't spend a lot — is there a kit that would cover the fitting and bulb without breaking the bank?
inparticular.ai
Completely understandable, and the good news is you only need to make this investment once if you buy the right thing. My clear recommendation is the Arcadia ProT5 Kit — it comes with the T5 HO controller unit and a 6% or 12% UVB tube included. For a 5-year-old adult dragon in a 4x2x2, get the 24 inch 6% version if you can mount it inside the viv (closer to the dragon), or the 12% if it'll sit on top of a mesh lid. The Arcadia T5 tube lasts 12 months at full output rather than the 6 months you'd get from a budget compact, so the cost per year is lower despite the higher upfront price. The 24-inch ProT5 kit runs around £35–40 on Amazon UK, and replacement tubes are about £12–15. Over two years you'll spend less than you did replacing compact bulbs. It's the most cost-effective setup available for this size enclosure.
That makes sense when you put it that way. Should I change anything about the basking setup at the same time, or just focus on the UVB for now?
inparticular.ai
Do both at the same time — it's worth it. For a 5-year-old adult beardie you want a basking spot of 40–42°C and a cool side of 25–28°C. A cheap halogen flood bulb from any hardware shop (40–60 watt PAR38 or similar) does the job perfectly and costs under £5 — there's no need to buy a branded 'basking bulb' at three times the price. Pick up a cheap digital thermometer with a probe, point it at the basking rock, and adjust the bulb wattage until you hit the right temperature. That's genuinely all you need. The Arcadia ProT5 kit plus a hardware store halogen gets you a proper adult setup for well under £50 total.
That's really helpful, thank you. I'll order the Arcadia ProT5 kit today.
inparticular.ai
Good decision — your dragon will notice the difference. One last thing: position the T5 tube so the basking spot sits within 25–30cm of the tube if it's inside the viv, or within 35–40cm if it's on top of mesh. That distance matters for how much UV actually reaches him. After a week or two you may see him become more active and start feeding more eagerly — that's a normal response to proper UVB. Five years is a good age and with correct lighting he's got plenty ahead of him.
