What does a bearded dragon need in its tank?

The minimum viable setup

If you're putting a bearded dragon enclosure together for the first time, work to the checklist below and skip the catalogue extras until everything here is in place. Bearded dragons are desert-dwelling diurnal lizards from inland Australia, and their requirements are unforgiving in two areas — UVB and heat — that most starter kits get wrong. Solve those two and most other care problems disappear.

Enclosure — the tank itself

A 4 × 2 × 2 ft (120 × 60 × 60 cm) enclosure is the absolute minimum for an adult bearded dragon. They are surprisingly active, terrestrial lizards that patrol the full length of their territory and need room to thermoregulate between a hot basking zone and a much cooler retreat. PVC-and-wood enclosures (Zen Habitats, Custom Cages) hold heat better than glass and allow proper UVB mounting; glass tanks work but lose heat fast and need larger wattages.

Hatchlings can start smaller but adults grow to 50 cm head-to-tail within 12 months, so most keepers buy the adult tank from day one and use décor to make it feel less overwhelming for a young dragon — cork bark, silk plants and a low ledge break the floor space into "rooms" without restricting movement.

UVB — the non-negotiable

Bearded dragons require strong UVB to synthesise vitamin D3 and absorb calcium. Without it, metabolic bone disease (MBD) develops within months — the single most common preventable cause of bearded-dragon suffering. The modern standard, supported by Zen Habitats' lighting guide and ReptiFiles' UVB explainer:

• T5 high-output linear tube — Arcadia Dragon 12 % or Zoo Med ReptiSun 10.0.
• Length covering two-thirds of the enclosure (e.g., 86 cm tube in a 4 ft tank).
• Mounted inside the enclosure, on the basking side.
• No glass or mesh between the tube and the dragon (glass blocks ~95 % of UVB).
• UV Index 4–6 at the closest basking surface — verified with a Solarmeter 6.5.

Compact "twist-in" UVB bulbs and mercury-vapour combo bulbs are still sold but consistently under-perform in independent testing. Replace T5 tubes every 12 months whether they look bright or not — UV output collapses long before visible light does.

Heat and lighting

Bearded dragons need a sharp temperature gradient: a very hot basking surface for thermoregulating and digesting, and a cool retreat about half that temperature. Achieve it with a halogen flood lamp (50–100 W depending on enclosure depth) on a dimming or pulse-proportional thermostat. Measure the basking surface with an infrared temperature gun on the spot the dragon actually lies on, not the air around it. Coloured "night-glo" bulbs are unnecessary and disrupt sleep — see the next section.

Run a 12-hour photoperiod on a mechanical timer year-round (some keepers adjust seasonally to support brumation). Avoid leaving the basking lamp on late — the photoperiod and the temperature drop together signal night to the dragon's circadian system.

Night temperatures

Bearded dragons need a real night. In the wild, inland Australia drops 15 °C or more overnight, and that drop is part of how they regulate sleep, hormone cycles and seasonal behaviour. In a heated room, switching everything off at night gets you to 18–22 °C (65–72 °F) — exactly right. No red bulbs, no blue moonlight bulbs, no night heat.

The only exception is a room that drops below 15 °C (60 °F): in that case a low-wattage ceramic heat emitter on its own thermostat, set to switch in only at the floor temperature, preserves the cycle without disturbing the dragon with light. For the same nocturnal/diurnal heating logic applied to a nocturnal species, see our leopard gecko temperature guide.

Substrate, hides and water

Pick one of three substrate approaches based on the dragon's age and your experience:

• Tile or slate — totally impaction-safe, easy to clean, holds heat well. Recommended for hatchlings and first-time keepers.
• Sealed wood or reptile carpet — safe but needs frequent washing (carpet traps faeces).
• Bioactive desert mix — 60 % play sand + 40 % organic topsoil, lightly damp at the base, with isopods and springtails as a clean-up crew. Excellent for adults; not recommended for hatchlings under 12 months because they may ingest substrate with prey.

Provide at least one cool-side hide (cave, hollow log, ceramic). Add a humid hide — a small box with damp sphagnum moss — during shed cycles. A shallow, heavy ceramic water dish on the cool side, refilled every 1–2 days, covers hydration during sheds and gives the option of bathing.

What to skip

Most starter kits include something on this list. Skip them and put the money toward UVB and heating instead:

• Coloured night bulbs (red, blue, "moonlight").
• Compact twist-in UVB bulbs.
• Loose calci-sand for hatchlings.
• Glass-lid covers between the dragon and the UVB tube.
• Sticky-strip thermometers (use a digital probe + infrared gun).
• Heat rocks (chronic burn risk).

Once the core setup is in place, the troubleshooting questions almost all disappear. The remaining ones — feeding, brumation, shedding — follow the same diagnostic pattern as for other species: check husbandry first, escalate to a vet on weight loss or specific clinical signs.