advice on keeping hard water off

so i had to get my black tib wet sanded because the sprinkler system where i live is old and full of super nasty sulfur and then it baked into my paint...

i now park away from the sprinklers but have a huge fear of my car being outside during day in hot sun..

what can i do now that they wet sanded it and applied wax? i bought an electronic buffer... i used to just clay bar but looking for proper steps to keep my black tib shiny and protected...