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F9 BARC Rust Stain Remover

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BARC from Front 9 Restoration is a concentrated, professional grade cleaner specifically designed to remove deeply embedded rust, fertilizer and orange battery acid stains. This is the best and most effective product we have ever found for removing these tough stains from concrete, pavers, brick, block, stone, vinyl siding and many other surfaces.

F9 BARC is highly concentrated and a great value. One gallon makes up to 3 gallons of ready to use cleaner! F9 BARC is also much safer to use than hydrochloric acids.



  • Safer than hydrochloric acid
  • Removes orange battery acid stains
  • Removes rust and fertilizer stains
  • Concentrated - Makes up to 3 gallons!
  • Spray / Brush Application
  • Coverage - See Detailed Info!


Tech Data Sheet

Safety Data Sheet


Detailed Info!

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Front 9 BARC

F9 BARC easily removes deeply embedded rust, battery acid and fertilizer stains from concrete, pavers, brick, stone, vinyl siding and many other surfaces. Follow instructions carefully for the type of surface you are cleaning.

Always test F9 BARC in an inconspicuous area before use to ensure compatibility and desired results!

If you plan to apply a stain, dye or sealer (except acid stains) after application be sure to neutralize and restore pH with before applying stain or sealer. Rinse thoroughly! Surface and pores must be clean, dry and free of all chemicals before applying stains, dyes or sealers. Acid stains are not recommended for use on surfaces that have been cleaned with F9 BARC.


Instructions To Clean Rust, Orange Battery Stains and Fertilizer Stains From Concrete:

1. Pre-Cleaning: Power wash concrete using a commercial grade pressure washer, our concrete degreaser and a surface cleaner. Rinse well. Cleaning the concrete first will open up the pores of the concrete and allow F9 BARC to soak in deeper and remove more of the orange battery stain than just applying F9 BARC alone.

2. After initial pre-cleaning, let the concrete dry completely.

3. USING A 1:2 DILUTION RATIO (1 PART WATER TO 2 PARTS F9 BARC) apply F9 BARC through our . Spray liberally and evenly to the entire pad of concrete. Do not "spot spray" on your first application. Use a circular overlapping spray motion. Spray from one side of the concrete pad to the other using a fine mist up to a uniform spray. High pressure low volume is recommended, so use a fine tip and keep sprayer fully pumped. Apply from control joint to control joint on the entire pad of concrete. Apply a bit more product on the areas with more staining. Apply as evenly and as thick as possible without letting F9 BARC run down the concrete. If F9 BARC does run down the concrete leave it alone. F9 BARC should begin to turn white and foam slightly.

4. Let concrete dry. Stains will disappear as concrete dries.

5. If spots remain follow directions in step 3 again. If not, proceed to step 7. It is better to go heavier on the first application and lighter on the second application. On the second application you may use less product on the areas with less staining and more product on the areas with stains remaining. It is acceptable to mist-spray on this application.

6. Let concrete dry. Stains will disappear as concrete dries.

7. A natural by-product of the reaction of this product and the concrete are light and dark mineral salts. Wet the concrete with water to reactivate the F9 BARC cleaner. While wet, lightly broom the concrete to help F9 BARC penetrate the concrete even deeper. Do not let concrete dry. Rinse LIGHTLY with a pressure washer to remove remaining surfactant. Do not use a surface cleaner here. Allow concrete to dry completely and evaluate results.

Warning: Applying F9 BARC to colored concrete or manufactured stone may remove color from the surface.


Instructions To Clean Specific Substrates:

Non-Porous Substrates: Sealed Concrete, Concrete Coatings, Clay Pavers, Tile, Painted Metal, Aluminum (not polished or chrome), Stainless Steel, Interior Pools and surfaces that do not allow water to penetrate. Dilute F9 BARC 2:1 (two parts Water to 1 part F9 BARC. This makes 3 gallons of F9 BARC from 1 gallon of concentrate. Spray a rate of 400 - 800 ft. per gallon. A light brushing with a may be required. Do not let F9 BARC Dry and rinse immediately following disappearance of stain.

Semi-Porous Substrates: Stucco, Plastic, Vinyl, Asphalt, Stone and others. Dilute F9 BARC 1:1 to 2:1. Spray at a rate of 400 - 800 ft. per gallon. Do not let product dry and rinse immediately following disappearance of stain.

Porous Substrates: Concrete, Bricks and Pavers. Require a heavier concentration due to porosity and the need for deeper penetration. Dilute F9 BARC 1:2 (1 part water to 2 parts BARC). Spray at a rate of 400 - 800 ft. per gallon. This applications requires F9 BARC to DRY INTO the concrete and lock in. Follow instructions listed on product and watch all F9 BARC videos before application.



Of course, having the right tools will make your job easier, so scroll down to see our recommended Sprayers, Brushes and Application Tools!




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