In What Order Should Pool Chemicals Be Added?

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Chemicals that neutralize acidity or alkalinity should be added to a pool first to establish the correct pH level for the other needed additives. Once the pH has been adjusted, calcium chloride can be introduced into the pool to soften the water, remove limescale and reduce cloudiness. Chlorine should be the last chemical added to the pool.

Test strips are available to determine chemical readings that indicate the type and amount of chemicals that need to be added to a pool. Testing should be done every other day to check pH levels. Water that is too basic is often cloudier and has problems with scaling and deposits. Water that is too acidic interferes with the sanitation effectiveness of chlorine. The ideal pH level is 7.2.

The amount of calcium in the pool must be balanced to reduce calcium deposits that can etch plaster finishes and harm vinyl liners and pool equipment. Calcium should be kept within 175 to 225 parts per million for vinyl pools and 200 to 250 parts per million for concrete pools.

Chlorine tablets or granules are added to pools for sanitation on a daily basis. Shocking the pool with chlorine should occur regularly to kill bacteria and to keep the pool clean and clear.