Complaint Review: Spa Depot

I bought an upgraded spa cover with a 5 year warranty.  After 3 years the stitching starting coming apart. I called the warranty dept and they asked that I send in a fe pictures.  After looking at the pictures they told me since the cover was faded I used too many chemicals and therefore the warranty is voided.  This is ridiculous as I take care of the hot tub to their specs 100 per cent.   Not sure how you void a warranty after looking at a couple of pictures.   The company finally offered a 10 percent discount on another one which is completely unacceptable.  After reading some other forums it appears this is a common complaint.