Care guide

Do Leopard Geckos Need UVB? Full Guide

Quick answer: Leopard geckos can survive without UVB using dietary D3 supplementation, but current husbandry guidance now recommends low-level UVB (roughly 2–6% T5) as best practice — it improves D3 synthesis, bone density, and natural behavior, and views on it have shifted significantly from older nocturnal-species advice.
Recommended bulbT5 HO, 2–6% UVB
Target UVI at basking area~0.5–1.5
Photoperiod10–12 hours
Strictly required for survivalNo, but now widely recommended

The old advice has been revised

For years the standard line was that because leopard geckos are nocturnal or crepuscular, they don't need UVB at all. That reasoning was based on incomplete evidence. Current research shows measurable benefits from low-level UVB exposure even in species that don't bask in intense sun, including improved D3 synthesis, bone density, immune function, and more natural activity patterns.

Recommended setup

A low-output T5 UVB tube in the 2–6% range, positioned so the basking area sits in a low ultraviolet index zone (roughly UVI 0.5–1.5), run on a 10–12 hour photoperiod. The bulb should only cover part of the enclosure, leaving a shaded area so the gecko can choose how much exposure it gets.

Is dietary D3 still enough on its own?

It can work, but it requires precise, consistent dosing at every feeding — too little causes deficiency, too much causes toxicity. UVB is now generally preferred because the gecko regulates its own D3 production by moving in and out of the UV zone, which is a more forgiving and self-correcting system.

What happens without any UVB or proper supplementation

Insufficient D3 from either source is the leading cause of metabolic bone disease — soft or deformed bones, tremors, and lethargy. If you skip UVB, calcium and D3 dietary dosing needs to be accurate and consistent.

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Leopard Gecko Enclosure: What You Actually Need

A single adult leopard gecko needs a 20-gallon long tank as an absolute minimum, with a 36x18 in (40-gallon breeder) footprint now considered the recommended standard — plus a secure lid, an under-tank heater on a thermostat, a thermal gradient, at least three hides, and a shallow water dish.

How to Set Up a Leopard Gecko Enclosure, Step by Step

Set up in this order: substrate, then heat source wired through a thermostat, then hides and water dish, then decor — and run the whole enclosure for at least 24–48 hours to confirm stable temperatures before your gecko moves in.

Leopard Gecko Tank Size Guide (Hatchling to Adult)

Hatchlings can start in a 10-gallon tank or tub, juveniles do well in 20 gallons, and adults need a 20-gallon long as an absolute minimum — with 36x18 in (40-gallon breeder) now the widely recommended standard, not just an upgrade.

Leopard Gecko Heating Guide: Equipment & Safety

Heat a leopard gecko enclosure with an under-tank heater and/or overhead heat source (halogen or deep heat projector) wired through a thermostat — a thermostat is mandatory, not optional, and heat rocks should never be used.

Leopard Gecko Humidity Guide: Ideal Range & How to Maintain It

Keep ambient humidity around 30–40% across most of the enclosure, with a dedicated humid hide raised to roughly 70–80% to support smooth, complete sheds.

How Long Do Leopard Geckos Live?

Leopard geckos typically live 15–20 years in captivity with proper care, with some individuals reaching 25 years or more — the oldest verified captive leopard gecko lived to roughly 28.5 years. Wild geckos live far shorter lives, usually 6–8 years.