The feeders do not move so when it goes to the bottom of them it is time to clean.
We use what is called the deep litter method, which is basically we let the manure build up and this provides a warm floor for the goats through the winter. You see as the manure breaks down it gives off heat. During the deepest cold of winter the floor is warm for the goats.
So we do not let the manure pile up to see really how high it can go.....it truly serves a purpose.
(But because of the all the rain we got to it a lot later than usual)