I installed a shallow well for my lawn irrigation. I am having a problem with the flow. I have 4 well points (10' long driven 30' total each). I have a 1 1/2 HP Meyer's pump and am told that should be plenty of water. The pump only puts out about 15 gallons a minute... about 1/3 of what it should. I have checked all of the joints that may be leaking on the suction between the points and the pump, with not luck. Can you give me a hand with this one?