This product eliminates trace metals that can cause staining and discoloration while preventing scale build-up due to calcium and other minerals that can clog up your pool system
Have pool water and fill water tested to see if metals are present at your water test center. Use Stain ID Kit to determine if stain is caused by metal. Gently rub the tablet on the stain. If the stain becomes lighter in color or is removed, RXSOL-31-3046-005 Stainfree should work.