Crested gecko stress stripes from overheating

Permanent stress stripes in a crested gecko are a real warning sign — they're telling you something is consistently wrong in the environment, and overheating is the most likely culprit. Crested geckos are unusual because they don't need a basking spot; they actually do best between 72–75°F during the day and struggle badly above 80°F. Getting heating and lighting right is the single most important factor in reptile health — most common reptile illnesses, from metabolic bone disease to chronic stress, trace back to incorrect temperatures. Before I can help properly: how old is your gecko, what size is the enclosure, and what do you currently have running for heat and light?

That setup sounds reasonable on paper, but the ceramic heat emitter is very likely the problem. Even on a thermostat, ceramic emitters can create warm air pockets in the upper third of the enclosure — exactly where crested geckos like to sit. They radiate heat in a way that's hard to escape in a tall vivarium. Can you tell me what temperature your thermostat probe is set to, and where exactly the probe is positioned inside the enclosure?

That's almost certainly your issue. The probe at mid-height is controlling the temperature there, but the top of that enclosure could easily be 5–8°F warmer — putting it right in the danger zone for a crested gecko. You need accurate temperature readings at multiple points before changing anything else. The product I'd recommend is the Inkbird IBS-TH2 Bluetooth thermometer/hygrometer. It's a small, accurate sensor you can place right where she hides at the top of the enclosure, and it logs temperature continuously to your phone so you can see exactly what's happening throughout the day and night. It's widely available on Amazon UK, consistently well-reviewed for reptile use, and costs around £12–15. Once you know the real temperature at her level, you can decide whether to reduce the ceramic emitter's target temperature or remove it entirely — which for a UK home in summer may well be the right call.

Honestly, in most UK homes during spring and summer, no — ambient room temperature is usually perfectly adequate. In winter, if your room drops below 65°F overnight, a gentle low-wattage heat mat on the side of the vivarium (never underneath, as crested geckos don't digest heat from below) can help. But many crested gecko keepers in the UK run no supplemental heating at all year-round. The IBS-TH2 will give you the data to make that call with confidence rather than guessing. Once you see what her actual temperatures are, I'd wager you'll be turning that ceramic emitter off entirely — and I'd expect those stress stripes to be gone within a few days.

Good plan. Check the top hiding spot, the middle, and the bottom and log them across a full 24-hour cycle so you get the complete picture. If you do end up needing winter heating, come back and I can help you dial in a side-mount heat mat setup with appropriate wattage for that enclosure size. Hope she's back to her normal colours very soon.