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D/2 Biological Solution - Removes stains from mold, algae, mildew, lichens and air pollutants

Original price $18.95 - Original price $209.95
Original price
$18.95 - $209.95
Current price $18.95
Size: 1 Quart Sprayer

D/2 Biological Solution - Removes stains from mold, algae, mildew, lichens and air pollutants

D/2 Biological Solution is a biodegradable, easy to use liquid that removes stains from mold, algae, mildew, lichens and air pollutants. It is effective on marble, granite, limestone, brownstone, travertine, masonry, terra cotta, concrete, stucco, wood, and other architectural surfaces including monuments, sculpture and headstones. A contact time of only 10 to 15 minutes followed by scrubbing with a soft nylon or natural bristle brush will loosen most biological and air pollutant staining.

D/2 Biological Solution is effective for removing harmful biological and air pollutant staining from many building materials including masonry, marble, granite, limestone, brownstone, travertine, terra cotta, concrete, stucco, wood, canvas and vinyl & aluminum siding.

Coverage: 250-350 square feet / gallon to remove medium staining

Check out all the of the users of D/2! Including The White House, The Veterans Administration, and the Congressional Cemetery. 

Safety Data Sheet     SPECS

Questions & Answers

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  • I was thinking of using this to clean a rough concrete walkway that is covered in moss and stained by mildew. What is the square footage that 1 gallon would cover for cleaning?

    1 Gallon cleans about 300 square feet

  • Can I just spray on the solution? Or do I also need a brush? I really just need to clean and not remove any growths. Thank you.

    Immediate Result Method

    1. Apply D/2 Biological Solution with a brush, roller, hand pump sprayer (garden style pump sprayer) or low pressure power sprayer.
    2. Allow undiluted D/2 to remain on the surface 10-15 minutes.
    3. Apply additional D/2 as necessary to maintain a wet surface.
    4. Scrub with soft nylon or natural bristle brush. DO NOT USE METAL BRUSH.
    5. Lightly mist with water and continue scrubbing.
    6. Rinse thoroughly with clean, potable water.

    Reapply if rain occurs within 12 hours of application.

    No Scrub/No Rinse Method

    1. Using a sprayer (pump-up, low pressure, or other,) wet the entire surface with D/2.
    2. Allow to air dry.

    D/2 works with the elements and results occur within one week to one month, depending on severity of soil. Reapply if rain occurs within 12 hours of application.

  • When do you expect D2 biological sprayer will be back in stock?

    We have them in stock now! When we run out of D/2 it can be expected that we will receive new stock shortly within a week or so.

  • Does this cleaner work on hard water build up?

    Hello! D/2 may not work on hard water staining. We recommend using the CleanStone or CleanStone Kit for this type of staining

  • Hello, is there any possibility to ship to Europe? Or maybe there is a dealer in Europe from where I could order too? We have a grave maintenance company providing services in all over Estonia and I would be really interested in your products.

    We are always happy to provide quotes to ship Internationally. Please send am email to and include your name + full shipping address + quantity of D/2 you are looking for.

    There are a couple of D/2 dealers in the UK as well, which you can find here.

  • How would I use this on a concrete driveway? Is ist safe for concrete and also the lawn that is on its boarder?

    Yes, you can definitely use D/2 concrete! It'll work very well to clean up any biological staining on concrete. D/2 could discolor / harm some of the lawn temporarily, but it will not damage the grass long term. If possible, try not to spray the D/2 directly onto the lawn, or you can also cover it with tarps, etc.

  • Does the qt that comes with the gallon have product in it to?

    Yes the quart is filled with the D/2 solution

Customer Reviews

Based on 9 reviews
Linda Glatczak
Amazing Results!

I used up my first order of D/2 and I can’t believe how well it works! I have used it on white headstones, gray marble headstones and red granite headstones, all with exceptional results. The black, green, orange and white crud growing on the stones comes right off. And the D/2 continues to lighten the stains with time. I’m so glad to have found this product. And I appreciate the helpful videos that show how to properly use it.

Suzanne Dorsett
excellent for grave cleaning

D/2 works very well to clean grave stones. It is effective on older sandstone and soapstone though the results are not quite as dramatic as you see on marble and granite. I've used the faster gentle scrubbing method as well as the spray and wait method; both work. Highly recommend.

Christine Nelson
If You're Serious, Then Get Serious.

I'm buying this in the 5-gallon jugs now so I can refill my cemetery volunteers' spray bottles. It's our preference for the stones we simply spray because we would rather not risk any added pressure by scrubbing. I expect it's how we'll maintain our restoration work in the years to come.

I did a little experiment on my own front walk comparing D/2 to Wet & Forget and another one that I forget the name of. It works best--give it the handful of weeks it needs to do its magic, then pull your eyebrows out of your hairline because it's makes a terrific improvement. I used it on my untreated exotic hardwood decks, too.


Excellent product—removed years of discoloration, lichen, and moss from granite tombstone.


D2 is excellent for cleaning headstones of course, but I have found another use for it - removing the black growth on my sandstone patio! Pressure washing was too abrasive and other cleaners didn't budge the growth. D2 cleaned 95%+ off right away and I'm looking forward to the improvement over the coming months.