How to Soften and Remove Scale

Scale Removal with LSI balance and SC-1000

Based on 10,000 gallons (37,855 L)

Scale Removal PDF



Carbonate scale is the consequence of water being over-saturated with calcium carbonate. This is measured on the Langelier Saturation Index (LSI). Carbonate scale begins to form when the LSI is above +0.30. To remedy this, the LSI needs to be placed in a safe, but slightly negative place (-0.30 to -0.01), to allow for the calcium to be brought back into solution. Using the Orenda App, the desired LSI range is yellow.

Scale, especially on tile lines, is often compounded by organic waste that makes it difficult to clean off. We recommend a combination of both SC-1000 to break down and dissolve the calcium carbonate, and CV-600 enzymes to break down and remove the organics.

Related: How to Implement the Orenda Program

You will need:

Day 1

  1. Raise the water level and/or turn on water features to soak the scaled area(s).
  2. Test the water chemistry, and input it into the Orenda App under “current levels”.
  3. On the right side of the calculator (desired levels), adjust the pH to 7.2-7.4, and find a way to get the LSI between -0.30 and -0.01. The LSI number should be yellow.
    1. Add the prescribed amount of muriatic acid, pre-diluted in a bucket of water, and poured evenly around the perimeter of the pool.
  4. Add one quart (32 fl.oz.) of CV-600 or CV-700 directly into the skimmer.
  5. Add one quart (32 fl.oz.) of SC-1000 directly into the skimmer.

Following Visits

  1. If the scale is still present, rub it with your fingers to see if it has softened or loosened. Brush and clean physically, avoiding abrasive tools that can scratch tile, etc.
  2. Re-test the water chemistry each visit, and document the results in the Orenda App.
    1. pH tends to rise on salt-generated chlorine pools, as well as when water features aerate the water.
  3. Adjust the water chemistry to be back in the yellow LSI range of -0.30 to -0.01.
  4. Apply maintenance doses of both CV-600 (5 fl.oz./10,000 gallons) and SC-1000 (3 fl.oz./10,000 gallons) directly into the skimmer.
  5. Add chlorine, as SC-1000 may have still impacted the levels.
    1. Maintenance SC-1000 dosing should not impact chlorine levels noticeably.
  6. Repeat the process on each visit until the scale has been removed.

Additional information

This process generally takes 2-3 weeks. SC-1000 gently breaks down carbonate scale, unlike acid. It needs time, and the water must be maintained in a slightly negative LSI state to dissolve the calcium. Always measure doses of chemicals and use proper safety gear.


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