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Pool Stain Treat

SKU: PST
(1)

Price range: $6.29 through $29.99

Stop scrubbing stains that won’t go away. Pool Stain Treat is a professional-strength formula designed to lift stubborn iron and organic stains from pool surfaces instantly. Whether you are dealing with “tea-colored” iron stains or organic leaf tannins, this fast-acting granular treatment dissolves them on contact.

Dissolves "Impossible" Stains Instantly: Specifically formulated to attack tough iron (rust/tea color) stains that regular chlorine and shocking cannot touch.
Works on Any Pool Surface: Safe and effective for gunite, marcite, vinyl liners, fiberglass steps.
No Draining Required: Save thousands of dollars by avoiding acid washes or pool draining. Simply treat the water and let the chemistry do the heavy lifting.
Long-Lasting Prevention: Acts as a powerful chelating agent, locking metals in suspension to prevent them from re-staining your walls and floor for up to 60 days.
Easy Spot or Full Treatment: versatile formula can be broadcast for total pool coverage or used in a spotting bag to target specific ugly spots on steps and deep ends.
Earn up to 1 point.

Stop Scrubbing "Dirt." Start Dissolving Metal

Those spots that won't brush off aren't dirt—they are metal. Pool Stain Treat chemically reverses the oxidation process, liquefying hardened iron scale and stains on contact. It lifts the stain off the surface instantly —no elbow grease required.

Restore Your Pool Without Draining It

Forget expensive acid washes or the risk of draining your pool. For a fraction of the cost of professional service, you can safely treat up to 20,000 gallons of water yourself. Keep your water in the pool and restore your surface finish to "like-new" condition in under 24 hours.

Safe for Vinyl, Fiberglass, & Plaster

From vintage gunite to modern vinyl liners, this formula is safe for all surfaces. It is specially formulated to remove the ugly "brown rim" on fiberglass steps. For specific rust spots (like fertilizer or bobby pins), simply apply locally using a spotting bag and watch the stain vanish in seconds.

Is your beautiful pool plagued by ugly brown spots, rust streaks, or “tea-colored” discoloration?

You aren’t alone. Most pool owners scrub for hours, only to realize those stains aren’t dirt—they are metal. And no amount of brushing will remove them.

Pool Stain Treat by United Chemical is the “secret weapon” pool professionals use to restore surfaces without the hassle of draining the pool or performing a harsh acid wash.

Why Chlorine Can’t Fix This

When you shock a pool with metal content (iron), the oxidation actually causes the metals to “fall out” of the water and stain your plaster or liner. Pool Stain Treat reverses this process. Its proprietary blend uses strong chelating agents (including Oxalic Acid) to lift the iron metal off the surface and bind it up in the water.

The “Miracle” for Fiberglass Steps

Fiberglass pools and stairs are notorious for developing a yellow/brown rim or “tea stain” over time. Pool Stain Treat is widely regarded as the gold standard for restoring fiberglass to its original, bright white finish.

How to Use Pool Stain Treat (Step-by-Step)

Always follow the label on the bottle for exact safety and dosage instructions.

  1. Prepare the Pool
  • Lower Chlorine: Allow your chlorine level to drop to 1.0 ppm or lower (0.3 ppm is ideal). High chlorine can destroy the stain remover before it works.
  • Balance pH: Ensure pH is between 7.2 and 7.6.
  1. Application (Choose One)
  • For General Staining: Broadcast 2 lbs (1 bottle) per 20,000 gallons around the perimeter of the pool.
  • For Spot Treatment: Pour a small amount of product into a sock or “spotting bag” and place it directly on the stain (use a pool pole to guide it). Note: Do not leave sitting on vinyl or colored plaster for extended periods without checking.
  • For Colored Plaster: Always pre-dissolve the granules in a bucket of water before adding to the pool to prevent bleaching the surface pigment.
  1. The Wait
  • Allow the product to circulate. Most light stains vanish immediately; heavier buildup may take 24 hours.
  1. Rebalance
  • Once the stains are gone, slowly bring your chlorine and pH levels back to normal. Do not “shock” the pool immediately, as this can re-oxidize the metals.

Additional information

WeightN/A
DimensionsN/A
Product Type

Stain Remover, Stain Preventative

Compatible Sanitizers

Chlorine, Salt, Bromine

Compatible Surface

White Plaster, Color Plaster (pre dissolve), Exposed Aggregate (pre dissolve), Fiberglass, Vinyl

Dosage

1 Spot Bag treats a 1 ft radius, 2lbs per 20,000 gallons (stain removal), 1lb / 20,000 gallons / month (prevention)

Size

4 oz. Spotting Bag, 2 lb. Bottle

1 review for Pool Stain Treat

  1. Debie Stockburger

    This stuff is the BOMB! OMG! I couldn’t believe it, years ago when a guy from the pool store who installed our pool, in 1998 came over. I was ready to pull my hair out because of the stains that looked like I poured a bunch of tea in. This guy got a bottle out of his truck and poured a little on the steps. IN AN INSTANT, THE STAIN WAS GONE!
    I had to get some. This was about 10 years ago. They charged around $55 for a 2 pound bottle then. When our San Juan Catalina pool was installed in 1998, we didn’t have staining issues. As the pool ages the “tea” stains get worse. This product and the United Chemical Stain Treat ( 2 different products)work in tandem. Around 3 or 4 days later I add Stain Treat to chelate the stains ( get them to clump together and get caught in the DE filter. These 2 products saved me a nervous breakdown!
    Our phosphates are high, this product may raise phosphates. I don’t do harsh chlorine shocks anymore. I pour about 1/3 bottle liquid shock and I use a very good non chlorine shock. I have to keep an eye on it. I have gotten to know my pool chemistry over 24 years. It looks as beautiful as the first day we used it! I have read that alot of fiberglass pool owners use this product.
    I recommend it highly!

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