Inside of coop it will fit nicely in a corner high enough and out of the way in an area with no droppings from above and it should last a long time. I drilled small holes in bottom of mine to make sure they don't hold water and OC stays dry. Hope it works as well for you as they have for me...
No, they are up off the ground at height about birds back screwed to the 4x4s used for fencing in pen. I have had them out for more than 7 years now work great for me, never have to clean just add new grit and OC.