How to Soften and Remove Scale

June 1, 2020

Scale Removal with 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). Scale begins to form when the LSI is above +0.30. To remedy, 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 make 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 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.
  6. Add chlorine, as SC-1000 will have depleted chlorine levels with the initial dose.

Following Visits

  1. If 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.


More Questions?




All information provided is intended for educational purposes and is not implied to replace consultation with a qualified pool professional. It is recommended that all information from this or any other source is to be performed assuming individuals performing these functions will consult local state and federal requirements before you act upon it in any way. While this site attempts to provide information that may be relevant to you, no guarantees are made that some relevant information will not be missed. We recommend you consult a local pool professional before acting. 

Subscribe to Email Updates

Recent Articles