I have a Well Mate WM9 tank and I'm not sure of the size but it's a pretty big tank (about 4 feet tall.) I only get about 1 gallon of water out of it before the pump kicks in, the pump starts at 40 lbs, runs for about 10 seconds and stops at 60 lbs just like it's supposed to. I pressurized the tank up to 38 lbs but after a short time I have almost no pressure again. Is it time for a new tank? How much water should you get from a full pressure tank before the pump kicks on?