durango

Looking to come up with something to remove water spots from a fiberglass fishing boat each time i use the boat. I have tried just the detail spray but it doesn't always take all the water spots off depending on what lake Im at. I know alot of guys that just mix distilled water and white vinegar to wipe down there boat but that solution doesn't offer much for lubrication to prevent scratching. So my question is has anyone tried mixing distilled water, vinegar, and rinseless wash to clean water spots. Thanks in advance.