Once you get the glass clean again, I know that some people use Rain-X to help keep the glass clean. I don't know if this prevents the hard water stains, or just drip marks. Anyone know?

I applied rain-x to new shower doors about 4 years ago. It has helped tremendously for water spots. We use a squeegee EVERY time after a shower. Our installer had said to just wipe the door with a towel. Others said to ditch soap for body gels because the talc in the bar soap stuck to the glass. So we squeegee daily, use body gel, and wipe the doors with a towel once a week. The bottom portion of the doors collect the most "grime" from shampoos etc. The glass still looks good. The one application of rain-x is still working. I don't think just applying rain-x will prevent the problems by itself.

We have different substrates and different deposits. Asking for help on the internet really doesn’t work. A California issue may not require the same action as a Florida problem.

Try to find a local solution, do you know any neighbors, store clerks?

This question seems to be asked nearly every week. Did you search for old threads and advice?

https://www.gardenweb.com/discussions/5490633/how-do-you-remove-mineral-deposit-on-glass-shower-doors#n=10

https://www.gardenweb.com/discussions/5601323/shower-glass-soap-scum#n=4

Well, thanks so much for your advice, to me, other posters, and the OP!

OP can read the threads I linked to find lots of advice if she wasn't able to find them on her own.