I have a horse I switched to renew gold a few months ago , while he is doing amazing and is a total new horse, had ulcer issues , a serious attitude and was getting dangerous , that is all gone , now that summer is here and we are riding him a lot he seems to be losing some weight. His diet is 1.5 renew gold 4lbs Timothy pellets, 2oz formula 1 noni blue, 2oz formula 1 papaya split between 2 feedings , and as much quality hay as he wants . Was looking for recommendation if I should add some grain? Or?? Just don't want him to get "hot" as two young girls ride him 

Instead of Timothy Pellets I'd do Alalfa pellets. 

Or alfalfa hay.

RG is pretty much meant to go with alfalfa hay. 

So your feeding 1.5 lbs of Renew Gold split into 2 feedings? I would do 1 lb each feeding and add alfalfa hay.

First thing to do is check teeth. If there is 1.5 pounds of RG in the diet and plenty of good quality hay, he should be carrying his condition fine. If it is not comfortable for him to chew as much as he normally would because it hurts to do so, that hay will not be properly broken up and will not have enough surface area to be processed properly in the hind gut. The result is that much of the nutrition passes on through with out being used. Even if teeth were done in the last six months, with the diet you are already feeding he should be carrying proper weight. Check the mouth.

Win