Weigh your grain. Feeding two scoops of grain daily is the equivalent to ???? 5 llbs, 10 lbs? who knows.
Take a small scale to the barn and weigh the grain and then feed the horse what is reccemended.
If you are trying to put weight on, after you weigh the amount you are feeding now, and it is say 6 pounds, up it to 10 pounds daily and see how it goes. Feed 3 times a day if possible. It will make a huge difference. Divide the total amount you are going to feed daily into 3 smaller feedings and your horse will do even better.
It is easy to feed a scoop of grain to a horse and then wonder why its not gaining weight but if the scoop is giving only 5 pounds per feeding and you should be feeding a minimum of 15 pounds per day there lays the problem.
This is what Triple Crown Complete has at their site for reccemended feeding:
Triple Crown Complete is designed for mature horses.
If feeding as a grain concentrate with hay, feed a minimum of 5 to 15 pounds per day for desired body condition.
If replacing all the hay in the diet, feed 1% to 1.5% of body weight daily