You don't mention how big your horse is. But I have a 16.2 Id who could live on fresh air. I have never limited hay. Short feed yes, hay no. I just don't believe in it and I don't think it does them any good. If the grass wasn't good I would say up 20-25lb... yes that much. At the moment he is out overnight and come in for about 4-6 hours a day and I don't think he eats any, but thats not to say he doesn't get a hay net full!
