I have a cage very similar to yours, and my tortoise always tried to escape that cage. One day he managed to push the cage door open, and we searched for what seemed like hours, and finally found him. But you might not be able to find your little tort again.
We did get a lock on it so he can't...
Sorry I should have mentioned it is only pretty dark at night, it is nice and light in the day time.
Before he moved rooms it was completely dark in his enclosure at night.
He is outside right now, and I just noticed some bubbles/foam in the front corner of both eyes. I literally just noticed this. Do you think this could be because of the light too?
Also, there is another light on in the room that he is in that we can't turn off. He still has lots of darkness in his enclosure and a hide that he never uses though. Could this be an issue too?
I will look into another light.