Yes Ma'am! I WILL be careful! It is useful, but dangerous. I've used muriatic acid before and the gas is dangerous to breathe as well as the liquid. It can really hurt you. I appreciate the warning. It's always better to be safe than sorry.

Where do I put the gauge? At the bottom of the filter canister there is an 3/4" threaded outlet. But it's before the pump, so I assume it could only measure suction. After the pump, there's a flex hose, 1 1/2" in diameter that comes up and outlets into the pool. To put a gauge there would require some plumbing modification but I guess I could figure that out. Is that where it needs to go?

Thanks for the welcome! I never thought about this before now, but I'm beginning to realize that this pool game is a serious hobby. Actually, MORE than a hobby for you all. What? A passion? I'm glad it is. I appreciate the tiresome help.