Hello all, new member here. From everything I've read here so far, this looks like a great site.
My problem is with my spa. If I close the valve on the skimmer suction line, and run the pump with only the main floor draining feeding it, everything is fine. However, as soon as I open the valve to start suction through the skimmer, the skimmer pot empties and air begins to be drawn into the system. Since the skimmer suction line draining the water, I know it's not plugged, so I don't understand why it's emptying the pot. My pool and spa are 8 years old, and this is the first time I've had this problem, so clearly, something has broken/leaked/changed. Any help would be greatly appreciated.