I use Barkeepers Friend.

You could try mixing half Dawn and half vinegar together anf spray. Leave on for about 10 minutes and rub with a rag or sponge and rinse. It also makes my fixtures shine like new.

CLR is a good product to use. Wear gloves as it can burn your hands if they come in contact with the chemical for any length of time. You can find it in your local food store in the cleaning isle.

Pam is spot on.. or shall I say off! Better results can be achieved by heaing up the vinegar in the microwave first, then add the Dawn (regular blue formula)

Thanks Becky. It's also leaves my fixtures shiny as new and they are 26 years old.

Hi Liz, I live in Az which is known for very hard water. As crazy as this sounds, I use furniture polish (orange or citrus) on my frosted glass shower doors. I just spray it on, let it sit for 10-15 minutes and wipe off with a clean rag/towel. Depending on how bad your hard water spots are, you may have to apply a second time. It works amazing....and smells good too.

Once they are cleaned you can apply paste wax and buff and that will seal for a while and hlep keep the water stains from forming again. You have to reapply every month or so but it helps.