Need help with mineral deposits on paint

[Gobstopp]

I believe they are mineral deposits. We run a landscape nursery, and often time park a loaded truck under irrigation, so the plants can get water. The water is the main issue. It comes from our well, and it leaves stains on everything, aluminum poles, wood, plastic, just everything. Today I went to wash the truck using the companies car wash concentrate, and it actually made it harder to remove the stain. So far I've had the most success using a dry paper towel on dry, unwashed areas. Once they have been washed with the car wash it becomes harder to remove, even when using a dry paper towel on a dry surface. Please help, what should I be using? Went to the local advanced auto and all their car washes were directed at a glossy polish finish, which would lead me to believe it would help much in removing the stain. Should i get a bunch of clay bars?
photo links
hood, before I used soap (http://i.imgur.com/E3e7MPM.jpg).

2 on the right are dry paper (http://i.imgur.com/ZCZGTmT.jpg)towel dry surface


car wash I'm using (http://i.imgur.com/kb7cRM0.jpg)

[dcjredline]

Search the AG store for MDR or mineral deposit remover. There are a few products for water spot removal

[Mike@DedicatedPerfection]

Welcome to AutoGeekOnline!

Is there any way to park just a loaded trailer under irrigation rather than parking the truck under it?

Stop using dry paper towels. You are doing more harm than good as you are now scuffing the paint. This will require machine compounding/polishing to remove the scuff marks you just installed with dry paper.

As mentioned above, search the site for water spot removers. Here is one.
Optimum MDR Mineral Deposit Remover, water spot remover for paint, water spot remover glass (http://www.autogeek.net/optimum-mdr-water-spot-remover.html)

[Gobstopp]

we have 2 trucks, a international 4200 22' flatbed, and a international 4200 16' dump truck. We try to only park the rear of the truck under irrigation, but since the irrigation heads are 25' high they have a lot of over spraw, especially if there's any wind. The company doesn't care about the paint too much because the trucks are considered replaceable equipment seeing as how we only own the truck for a few years before upgrading, so scratched, scuffs, not really a problem, but this brown mineral deposits just make the trucks look bad. Ordered some mdr, hope it works, because every review I see only uses it on small water spots. I've tried clr, doesn't do anything for the paint. Best solution I've found is vinigar based cleaners for the windows, but it doesn't help on the paint