Hi Courtney, Thanks for getting back to me.
Salt water pools use common salt which converts a portion on the salt (the chloride part) to chlorine. The salt make the water ?soft? and the remainder is a mineral either calcium or magnesium. These minerals are chalky and white in color.
So the good news is that I do not think this has permanently damaged the fabric.
Before we get started, I recommend you check the car manufacturer?s care and instructions to see what they recommend for cleaning the car seat fabric in case they list any concerns about color-fastness or other limitations.
Are we all set then?
Okay- First take a whisk broom, and vigorously sweep as much of the white stain away as possible. It may not look to you like it is helping much, but that?s okay. The purpose is to remove/ start to dislodge as much of the mineral build up in the fabric as possible.
Then I?d get some plain white straight vinegar, pour a little bit on a clean white cotton towel, and pat or dab the stain with the vinegar. The vinegar will help dissolve the minerals, and make the removal from the fabric easier.
I know the vinegar smells, but it is really effective, safe to use and smell dissipates quickly, it is also a natural deodorizer too.
Use a small steam cleaner with cold water (with a hand attachment) and using as little water a possible to avoid soaking the seat, go over the stain a few times. The white stain should come right up. If when it dries you see a remaining stain you can try the vinegar/water method again.
Though a steam cleaner extraction is preferable, if you do not have one available, you can also dab with the vinegar and wipe with a cotton cloth that is damp with cold water. This should work, but it is not quite as effective in removing those minerals out of the fabric. Be extra careful to avoid fraying the fabric by excessive rubbing.
I hope that helps.