Natural Way to Remove Metal Staining

Stainfree is an all-natural stain remover that contains industrial strength ascorbic acid. It quickly removes metal staining without adding phosphates to your water. It is ideal for treating staining on all pool surfaces. Use with Natural Chemistry's Metalfree™ and you have the ultimate 1-2 combination for stain fighting!

  • 100% ascorbic acid- premium stain fighter!
  • Safely removes metal stains from pool liners and finishes
  • Quickly removes stubborn stains
  • Compatible with all sanitizing systems


Directions for use:

Note: Operating the pool for a couple of days without chlorine can create an algae concern. Follow your pool dealer’s recommendations on steps you can take to protect your pool from algae during this metal stain removal process.

  1. Balance pool water chemistry before using Stainfree: pH:7.2-7.6, Alkalinity: 80-120ppm, Calcium Hardness: 200-400ppm, CYA below 50ppm, Phosphates: below 100ppb Note: Stain removal products work best when the pH is on the lower side of acceptable range (7.2)
  2. Important: Before starting the metal stain removal or water discolouration process (step 4), a pulp based filter aid must be added to cartridge and sand filters. DE filters must be properly charged.
  3. Lower chlorine level to 1ppm or less (A high chlorine level or adding oxidizing agents during the process will prevent Stainfree from working as designed.)
    • Surface Staining: If the surface is stained, add 454g (1lb) of Stainfree per 10,000 gallons as close to the stained area(s) as possible with the pump off overnight.
    • Water Discolouration: If the entire body of water is discoloured, put the pool on recirculate, add 454g (1lb) of Stainfree per 38,000 litres to the pool evenly around the edge. Let the circulation run for one hour. After one hour, shut the pump off and let sit overnight.
  4. Before turning the pump back on, brush the pool walls and floor thoroughly.
  5. Turn the pump back on and add Metalfree evenly to the pool around the edge at a rate of 1L per 75,700 litres.
  6. With the pump still on, vacuum the pool walls and floor very thoroughly.
  7. After vacuuming, clean filters: Sand filter- backwash for at least 3 minutes and then rinse for 2 minutes Cartridge filter- clean filter and filter tank thoroughly DE filter- backwash and recharge with DE
  8. Test and rebalance water. DO NOT SHOCK THE POOL FOR AT LEAST 1 WEEK.
    • Note: If chlorine level is low, add small amounts of chlorine. Do not exceed 2ppm. For salt generator pools, a granular shock is recommended instead of turning the generator to its boost (superchlorinate) function after the recommended 1 week.
  9. Use Metalfree as a weekly maintenance to prevent future metal staining. Apply 1 capful (120mL) per 38,000 litres once a week.

Do not swim until stain procedure is complete and normal chlorine residual is established.

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