How do you keep your horses from getting too plump?? I try to make it so my sensitive stomached/ulcer prone horse does not go long (or at all) without something to nibble on. Mine def look like a wide load

Also, I board but take care of my own horses and only go out once a day. My barrel horse gets a handful of TC senior and alfalfa pellets so there is something to mix her supplement with. Most of the time they are fed using a slow feed hay net so it will last. 

Suggestions? 

I feed Alfalfa am/pm and keep their inside feeder full of orchard grass... the grass hay has less calories and gives them something to pick on. I weigh my alfalfa to keep the calories in check. I feed 2nd cutting... 

Both my horses eat a grass hay. I pack a hay net full once a day and it generally last 24 hours till I return to ride and repack then and so on. They learn to pace themselves once they figure out that they will have it there all day. I pack mine with like 4-5 flakes mind u there smaller flakes most the times but that accommodates dinner breakfast lunch and then I return. 

I'm with you! Mine can't have free choice- too fat! Wish they could but they can't.

I keep grass hay out 24/7 - in a large feeder in their respective pastures during good weather, and in the feeder in their stalls during bad weather.  They are in separate pastures with their own large stall that they can go in and out of all day.  I feed 2 and 3 flakes alfalfa once a day.  My older mare has always been a harder keeper and when I started doing this she really bloomed and looks great.  She will not overeat.  My yearling is soggier, but I do the same things with her and she is figuring it out.  I agree with whoever said that they seem to learn to pace themselves better when they know there will always be food avaliable.

I would rather have a happy, healthy horse with a hay belly than a leaner horse with digestion problems any day. Horses are made to graze 17-20 hours a day. Horses were not made to eat high quality grass all day, but a variety of grasses of lower quality than the pasture grasses developed for fattening of cattle. So feeding good quality hay mixed with a little lower quality is recommended. It's very important for mental and physical health that they be able to do graze throughout the day/night. And yes, it takes time, but they will learn to not overeat. Once they trust they will have food in front of them for whenever they need it, they will slow down and slim down. 

Using a slow feed hay net can help as well or a grazing muzzle.