I think I need a new pressure gauge for my sand filter; the gauge never moves. It will register 0 with the pump off but when the pump is on it never goes above 5. It's the gauge that originally came with the system. Given the fact that Intex has proprietary sizing on all of their equipment, I am wondering if the gauges sold on the tftest kits site will work. Has anyone here used one of these gauges on an Intex pool?