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Lessons 7: Testing Dissolved Solid

Total dissolved solids (TDS) is the total of all of the dissolved things in water including hardness, alkalinity, cyanuric acid, chlorides, and other chemicals found in the pool. If the TDS levels are above 1500 ppm, the water turns rusty and cloudy. Can you test the amount of dissolved solids that are in the pool water?

Doing the science

  1. Start the Pool Bacteria Simulation by clicking on the "Sim" tab.
  2. Click on the "Chlorine" and "Dissolved Solid" checkboxes on the section labeled "Tests" and adjust the "Number of Swimmers" to 5.
  3. Click on the "Run" button.
  4. Click on 0, 6, and 12 under "Time (hours)" to find the chlorine level and dissolved solid level at that time period. Record them in Table 1 below.
  5. Click on the "Reset" button.
  6. Click on the "Chlorine", "Dissolved Solid", and "Cyanuric Acid" checkbox on the section labeled "Tests" and repeat steps 3-5.
  7. Repeat steps 2-7 with the number of swimmers designated in Table 1.

Table 1.

Number of Swimmers

0 Hours

6 Hours

12 Hours

Chlorine

D.S.

Chlorine

D.S.

Chlorine

D.S.

5

5

with Cyanuric acid

10

10

with Cyanuric acid

15

15

with Cyanuric acid

20

20

with Cyanuric acid

Do You Understand?

  1. Is there a relationship between the dissolved solid level and the number of swimmers? Explain.


  2. Is there a relationship between the dissolved solid level and the chlorine level? Explain.