Lighting for three gecko species

Getting heating and UV lighting right is genuinely the single most important thing you can do for your reptiles — the vast majority of common illnesses, from metabolic bone disease to respiratory infections, trace back to incorrect temperatures or inadequate UV. Three gecko species in one home is brilliant but it does mean three different setups, because their lighting and thermal needs vary significantly. Which three species are you keeping, how big are each of the enclosures, and what lighting do you currently have running in each one?

Right, so no UV on any of them — that's the priority to fix first. Each of these three actually has quite different requirements. Your leopard gecko is crepuscular and needs low UV, around UVI 1–2, so a 5% or 6% T5 tube is ideal. Your giant day gecko is a whole different story — it's a sun-basking species that needs UVI 3–4, so a 6% or even 10% T5 depending on how far the basking spot is from the lamp. Your crested gecko is the interesting one: they were historically kept with no UV, but current evidence strongly supports giving them low UV around UVI 1–2, and they genuinely benefit from it for D3 synthesis. Can I ask — are you open to running T5 HO fluorescent tubes, or were you hoping to stick with compact bulbs?

The Arcadia T5 HO range covers all three and it's genuinely the best UV technology available for reptiles in the UK. What I'd recommend is this: for your leopard gecko, the Arcadia Forest T5 6% UVB — it replicates the shaded, low-UV environment they'd experience at dawn and dusk. For the crested gecko, the same 6% Forest tube works perfectly. For your giant day gecko, you want the Arcadia Desert T5 12% UVB — day geckos in the wild bask in intense tropical sun, and the 12% gets you the UVI 4+ levels they need at a sensible mounting distance in a 90cm tall viv. The key product to start with is the Arcadia T5 HO ProT5 Kit, which comes with a reflector and ballast — you'd just choose the correct tube percentage when adding it to your basket. The reflector alone doubles usable UV output, which is why I'd always recommend the kit over a bare tube and a budget fitting.

Yes, and this is where they diverge again. Your leopard gecko needs a warm side of around 30–32°C with a cool side at 24°C — a halogen spot bulb or a deep heat projector on one end handles that well, and you should not use heat mats on the floor as primary heating since leos regulate temperature through their belly in the wild. Your giant day gecko needs a basking spot of 32–35°C with ambient at 26–28°C, so a small halogen spot positioned at the top of the viv is ideal. Your crested gecko is the easy one — they need no basking spot at all and actually do badly in heat above 27°C, so your ambient room temperature is usually enough, and you keep them away from any heat source. Does your current setup have any thermostat-controlled heating, or is that something you need to sort at the same time?

Good plan — get the UV sorted first and then add thermostats before the colder months. One last practical note: UV tubes degrade before they visibly dim, so replace them every 12 months even if they still look bright. Mark the date on the fitting when you install them. You're setting all three up properly now, which makes a real difference to long-term health. Good luck with the collection.