I suggest moving the
UVB light so that it is sitting next to the basking light and shining directly downward rather than at an angle. It looks like you have a compact
UVB light in the dome fixture and a T8 sitting on its side on the outside of the glass. I would remove the T8 and either put it inside the tank attached to the ceiling (shining down and without any plastic in front of the bulb) or use just your T5 tube (I don't see this in the photo, is it on top of the enclosure?) The glass from the tank is intercepting all of the
UVB light from the T8 on the side so it is likely just causing irritation due to the angle.
If you don't have enough space overhead for the lights, you can try suspending them overhead using adjustable lamp stands. I use them and they work very well for the dome fixtures.