Nutrient lockout or deficiency with well water

I’m a new outdoor grower in northern ca on deep well water that is very hard. I have an RO filter and have tried everything for years. Flushing, supplements, different kinds of strains, RO and supplements. Nothing is succeeding. I can test the PH, but then what filter do I use when I figure out all my plants are dying because I have salty hard water and the RO version produces a deficiency? We don’t get enough rain to collect water. I could haul in recycled water. Nightmare. Switch to hydroponics, which I know nothing about. I need help. I researched “drops of balance” but I don’t need drops,I need to “purify” a 5K holding tank of well water and be able to grow before I die! I have five acres of land and very unhealthy plants all around. Succulents and peppers do great. HELP ME!!!! PLEASE.

RO water shouldn't be having such a dramatic effect on your plants. You should tell us more about your grow, what nutrients you are using, etc, to help nail down what the problem is. Are you PHing and testing your EC after you mix up your nutrients?

Are you putting cal/mag back into the RO water?