What do I do for colic for my horse?

My horse had just colicked yesterday a very mild case, gave him some bute and after about 4 hours gave him some gr hay, no grain, he pooped and was fine. I am reading about bran mashes and I here yes bran and no bran. I give him horse and mule as grain and was wondering would switching him to a pelleted food maybe help. You can ask 100 people and get 100 different answers around here. So just looking for other ideas. By the way he is a 5 yr gelding.