I just bought a new house with a 9 foot hybird pool I would say about 20 years old. the side walls are fiberglass and the bottom bowl is concrete, i am in the process of trying to drain the pool since it need to be repainted, I know this is not a fix but a re plaster job is out of the question this year. The pool sits in a very low point in the yard and once i get to about 4 foot of water left in the pool the hydrostatic valve opens up and lets the ground water back in (I know its doing what its designed to do ) the problem i am having is getting the ground water out from under the pool. By my pool pump there is a 1.5in PVC pipe that not connected to the pump in any way. I tested this line and it looks like it goes under the pool shell to remove ground water. I Have an old pool pump 1.5 hp that I connected to this line to try and remove the ground water but i cant keep the pump primed long enough to created enough suction to get the ground water up to the pump (about 6 feet vertical rise) If anyone had any tips or know what to do in this situation please let me know