You can get a brighter UV output than a T8 lamp with an Arcadia D3 UV Reptile Lamp from Swell Reptiles - far more efficient than older models of fluorescent tube and with a 6% UV output, this model is perfect for rainforest reptiles such as chameleons, water dragons and crested geckos.
T5 tubes are the update from the older T8 fluorescent strip lights, using less energy than older models but giving you're a brighter more intense UV light for your reptile to benefit from. These 6% UV lights simulate the ultraviolet light from the sun, filtered by the rainforest canopy, giving your reptile a dose more accurately resembling what they would receive in the wild.
These Arcadia D3 Reptile lamps help your reptile generate vitamin D3 when they bask under it, allowing them to absorb the calcium in their diet and use it to build strong skeletons. This is an extremely important part of reptile keeping, and without D3 UV and calcium, your reptile can develop problems like Metabolic Bone Disease.