Thank tou very much for the responses, and I will start soaking his cubes. He is pretty thin, and his general condition is fairly bad. He's limping on one hind and has a bad eye infection. However, this person is not my boarder, and I am not actually responsible for feeding him. I have arranged with the boarder for me to look after him since the person that does board the horses doesn't know anything. The guy who boards them just wants to make money, and he has fed the horses mulch, dry beet pulp, wrong amounts, etc... so I just told him that I have no problem feeding this other guys horse and the boarder is happy that I'm doing it. He only got the pony last week, bought it from a boarding stable and he came in this condition. I'm pretty sure they just completely lied to him about everything in order to sell him the pony, but since being here he is already coming around.