We bought this house several months ago and the pool is approximately 10 years old. I've always thought the pressure coming out of the jets on both the pool and spa was kind of weak. I've recently noticed that a couple of the jet eyeball fittings were completely gone and so it's just like bare PVC ends going into the pool and spa. I realize that by having these opening wide open, it lowers the pressure coming out of the other jets. But I'm not exactly sure if that's the only problem. How can you tell if your return jets are producing enough pressure?