Tony wrote:
My bladder type water tank is rated 20 gallons.

With no water I have 26.5 lbs of air pressure in tank.

The pump cuts in at about 28lbs. and out at about 51lbs.

With the tank full I only get 6.75 gallons of water before the pump runs
again. Is this right? If not, what's wrong?

Thanks

Thanks everyone, I'll check into some larger tanks. Large is no
problem, I've pumped an estimated 5000 gallons out of it in about 6
hours. Note: I extended the 1" main to a 1" frost proof spigot so
running the hose full blast keeps the pump running full time instead of
turning on and off. Only problem with that was getting brown water with
small gravel until it sits for some time. The one time the gravel was
enough to block the spigot decreasing the flow, and also making it
impossible to turn off! (lucky I put it's own cutoff valve inside)

And as far as pumping so much water and how it will effect my well. My
ex FIL worked for a municipal water company for 30 years and now and
then they would basically try to run a well dry. The reasoning is
because in all the tiny little cracks and crevices in the sides of the
well is sediment, and running the well so low helps wash out the
sediment and actually improves the wells capacity after some time.