I have one of those float type automatic cut off things in a long trough (actually, a piece of plastic gutter, with the end caps on it. When it gets dirty, I pick it up (its pinched in place, but not screwed in place and wash it out, then put it back. It sits on some broken concrete.
I also have an automatic dog watering bowl, also attached to a hose. It hase to be emptied every day to get the sand/dirt out of the bottom, and allowed to refill.
Both hoses are attached, eventually, to a 275 gal tote with gets rain water viaa gutter on the side of my barn.