Walk to your enclosure. If you cannot answer what type of UVB bulb is installed and when it was installed, write both on the bulb's side in pencil today.
Five UVB mistakes we still see in 2026.
Coil bulbs. Glass between bulb and animal. Mounting too far. Twelve-month-plus replacement. Over-bulbing in a small cage. Easily fixed; quietly fatal.
Coil bulbs produce too narrow a beam to create a usable gradient and have a long history of corneal damage cases. Replace with linear T5 HO. Glass between bulb and animal blocks UVB; a screen ceiling does not. Mounting too far drops UVI below the threshold the animal needs.
The two we still see weekly: bulbs in service past twelve months, and twelve-percent bulbs in 24x24 cages where they produce dangerous peak UVI. Six-percent in a 24x24, twelve-percent in a 36x36 or larger. Replace at twelve months on the calendar.
DSQUARED Reptiles — Living Art. Curated Genetics.
From the field notes archive.
The morning baseline photograph.
A single weekly photo, taken at the same hour and angle, will tell you more about your care than any forum thread ever could.
Tightening screen tension on a year-old cage.
After twelve months of misting cycles and live plant weight, screen panels sag in ways that quietly compromise climbing surfaces.
Building a Ferguson Zone 3 UVI gradient.
Panthers want a UVI gradient running from roughly 0 in the deep canopy to 4 at the basking spot. The fixture choice and mounting matter more than the bulb brand.