PO, most country folk would pay dearly for a well like yours, it's more than capable of maintaining your water level to some degree. Agitate it before it flows in for oxygen, and keep in mind evaporation on a hot summer day can take away more than you can produce. If you're pond is 18-20 feet deep, that's 13 million gallons you're holding now, you probably only need to suppliment water the size of a swimming pool (15,000 gallons) unless your pond is leaking. Barring a summer drought.
