Ryan I came up with 2.36 GPM 24/7.

325828 Gallons per acre foot/ 12"= 27152 gallons per acre inch

27152 Gallons * .5 acre= 13576 gallons

13576 Gallons * .25" evaporation= 3394 gallons

3394 gallons / 1440 minutes per day= 2.36 GPM