I am getting my boat ready for the season and there are some pretty bad water spots, they don't wax off or come off with vinegar. The only thing that seems to work is calcium and lime remover, but that stuff seems pretty corrosive, will it be bad for the gel coat? What are some secrets that other people use?

Time to get out the buffer...

coral car wash works really well on our boat. took spots right off. spots that vinegar wouldnt.

Once your boat is cleaned up. Get a couple of microfiber towels and use them to dry off your boat afterwards. The microfiber towels have the effect of giving your boat a good scrub as they dry your boat. I can dry a VLX with two of them, then move to the windows and chrome, works great everytime. If you have a Costco nearby they sell a large pack of them in yellow.

Polishing compound, then wax.