Siphon system if you have an elevation change that works for you on your property?
Drain system to a float valve?
If you ahve to have an elevevation change then a small generator to run a centrifugal pump to a fill a cistern that then fills a stock tank with float valve by gravity.
Or solar pumping to the cistern, then to stock tank via a float valve.
As
@ponytug mentions above, a pump controller (Linear current booster/DC to DC converter) will aid a solar pumping during cloudy conditions or at dawn and dusk. A pump controller will give you anywhere from 20% to 50% more water under low light conditions.