A good feeder is one that the animals can get the food out of without making a mess or wasting lots of hay. Also, a feeder should be built in such a way that the animals can't get into it and take a nap in it.
I noticed that the gates (which have some livestock fencing attached so that kid goats can't escape) were about 8" away from the wall when latched open. Hmmmm......, I wonder if a flake of hay would fit between the wall and the gate? If it did, voila! an instant feeder!
It turns out that 8" wasn't quite enough space so I tied some baling twine (otherwise known as 'the farmers friend') to the eye bolt in the wall, then latched the gate to the baling twine. It gave it just enough room to fit in some flakes of hay! We have used the new 'feeders' for about a week now and have really liked them. The goats can pull out bits of hay without making a big mess. It will also be easier to clean up inside the stall rather than underneath the feeder that is outside. The outside feeder is on dirt, our barn has mats since it was originally designed for horses.
The other great thing about the door feeders is that the taller animals can eat over the shorter animals. The goats can eat over the top of the sheep, and the llama and huarizo can eat over the top of the goats. In the evening there are about 4 flakes of hay in each gate, two flakes on top and two flakes on the bottom. Everyone can reach some dinner in one stall or the other!