He is already on prebiotics and I have ordered supplements that have prebiotics, probiotics, enzymes, L-glutamine, and soothing agents. Also on the way is calming supplement in case he is stressed. His feed and the omegatin are supposed to be low in starch and in sugar. His "training" is very light. Actually, I have not ridden him in a week and that has done nothing. I really just don't know. The tests show hindgut bleeding but nothing in the stomach, although he has not been scoped. The vet does not seem to think anything needs to be done additionally, but this cannot be healthy for him.
Well gosh no, hind gut bleeding can't be a good thing and would indicate that the digestive process that happens there would be compromised.
How long have you given the pre, probiotics and all that? The entire time you've owned him, or is this just recent. I'm just wondering, have you given these things enough time to work? You may need a month or more to see a physical change.
Do you have access to a specialist, or can you get a reference for a specialist?
I hate to say it, but if too much damage has already been done...
Another thing you might try if you've got nothing left to try is acupuncture.
Oh, and have you had blood pulled to see that his nutrient levels are correct? And you still haven't said what the base ingredient is in his grain.