Bought a house in Dec 18, it has a 20x40 in ground. Lurked TFP, got the app, opened pool last weekend been using BBB method and been going okay so far. I’m just confused as heck as to what my valves control. I just turn them until I have good suction at both skimmers, pretty sure the return suction at the bottom of the pool is off. When I open all the valves hoping to have suction at everything the suction is so weak on the skimmers. My pump was loud today after vacuuming and pressure was up to 15ish, it’s usually at 8-10 so I backwashed. Like I said I’m a noob. Didn’t do anything to the valves so when I went back to filter mode a bunch of diarrhea looking Crud shot out of both supply jets. The pool is like 30 years old and the labels are long worn off the valve plumbing. I hate not knowing what the valves do it’s killing me, I’m a cheap Rear I’m not calling a pool company to explain the valves to me. This seems a pretty basic setup if anyone would kindly inform me what is what I’d greatly appreciate it.