Thanks for the reply
It's definately not bladder stones, his last x-ray was 4 months ago and he had no signs of building one up again.
It was dehydration and poor care from the previous owners that caused the first. He was in very poor shape with advanced MBD when I got him, I've worked closely with a specialist vet to get him healthy again over the last 3 years and he's been given a clean bill of health.
I moisten his substrate twice a week in hot weather and he has a 30min soak every other day (because i seem to have the only tortoise in the world who loves a warm soak) in which I've seen him drink regularly.
All bowel movements, urination and urates are normal. Hes not straining to poop.
It's simply that the substrate keeps sticking to his hemipenes and causing him discomfort :/