Hi, Yeah as suggested you really need to move the lamp into the hot end so that the hot end has heat and light and the cool end has cool and shade
You really do also need a good reflector. An unreflected lamp is wasting two thirds of the total power output.
lamps must never be hung down the wall like this also. It really does present a risk from glare to the animal. Use a good reflector and mount it to the roof.
John Courteney-Smith MRSB.
Arcadia Reptile; Head of Science and Innovation
BRAND NEW BOOK out now. The Elements series; Part 1- FIRE, The Sun, its Use and Replication in Reptile Keeping
Find us on facebook under "Arcadia reptile"