I use fluoridated tap water. I've never taken ph. My plants are in an unholy combination of peat moss, compost, perlite, and whatever raised bed soil I got to top them up from Lowes. They're in pots outside, subject to suboptimal temperature, humidity, diseases, pests, etc. I use Miracle Gro (all purpose and bloom booster) to feed, and I do it when I do my veggies bc I haven't got time to faff around. I'm going to top dress with Down to Earth cactus fertilizer and do a little cal mag supplement this week for the first time since May.
According to the pros, I'm doing everything wrong, badly, and breaking all the rules, but my autos are twice the size they were last year. They're flowering like gangbusters. I threw in two photoperiods, and they're even bigger, and they haven't even started flowering yet. I can't figure out how to share photos sufficiently anonymously, otherwise I would. But most of gardening is dirt management. You're hauling dirt, refining the nutritional content of your dirt, and managing the dirt's moisture. Plants know what to do, once you put them in the dirt and add light. Life, as they say, finds a way.