Thank you perfectly_flawed for answering. Sadly I've seen him chew it myself and had to rush to stop him

Please remember that I am in South Africa so we are limited to a few bands.
Basking area: 38 degrees Celsius.
Cool area: 28 degrees Celsius.
Thermostat: It is one of those stick on ones. Got one stuck on both ends of the tank.
UVB light : CH lighting F18 T8/ reptile 2.0 I am not sure of all the ratings, it is the one the pet shop sold me. The bulb is about 25cm away from him. I am busy varnishing his new cage which means that the bulb will be about 50cm away.
Bugger gets live crickets every day; I put about 20 in his cage when I leave for work. Plus he gets some green. The greens are: Watercress, butternut, cucumber, green beans and mint. I sometimes give him two earthworms as a treat. My husband thinks that maybe he thinks his tail is an earthworm? When I first got him he wouldn’t eat anything but earthworms, he really loves them! I have also given him daga worms.
I give him a calcium supplement in his salad every day.
I am using a synthetic plastic floor for the bottom of his cage, almost like plastic tile flooring.
I try and bath him every Friday.