Chlorine Comparison

• Liquid bleach contains sodium hypochlorite, which is the liquid form of chlorine. Standard pool chlorine is usually dispensed in chlorine's solid form, which is calcium hypochlorite. Sodium hypochlorite and calcium hypochlorite differ only in the form (liquid or solid) and strength of the chlorine each contains. Liquid bleach is about 5.25 percent chlorine by volume. Calcium hypochlorite can contain up to 92 percent chlorine by volume. The average chlorine strength in standard pool chlorine is about 65 percent, though.
  
  

Chlorine Levels

• In a swimming pool, the recommended chlorine level from any source is 2 parts per million (ppm). 1 ppm to 3 ppm of chlorine in a swimming pool is a good working range for pool owners to maintain. 1 gallon of liquid bleach can deliver 2 ppm of chlorine level per 30,000 gallons of water. By comparison, it takes about a pound of calcium hypochlorite pool chlorine to deliver the same 2 ppm chlorine level in a pool.
  
  

Bleach Usage

• The manner in which liquid bleach is introduced into a swimming pool is important. The recommended introduction method involves pouring liquid bleach into the swimming pool's skimmer. When bleach is put into the swimming pool's skimmer, it goes into the pool's filtration unit. From the swimming pool's filtration unit, bleach mixes thoroughly with water and spread throughout the pool quickly and safely. Monitor pool chlorine levels with a testing kit, and then periodically add bleach as needed.
  
  

Dosing Frequency

• At minimum, you should check a swimming pool's chlorine levels twice weekly using a good all-purpose pool testing kit. Whether you're using liquid bleach or standard calcium hypochlorite pool chlorine, it's generally not necessary to use large amounts in a pool. Just test for pool chlorine levels and add only enough to keep a swimming pool at about 2 ppm of chlorine. If you add too much bleach, though, just let chlorine levels decline over a few hours and retest again.
  
  

Considerations

• Swimming pool pH balance is important no matter what kind of chlorine you use. The recommended pH range in a swimming pool is 7 to 8. Try to shoot for a 7.4 to 7.6 pH range, which is optimum. Chlorine works best in a pool when that pool's pH balance is at optimum levels. You can raise pool pH levels by using either soda ash or baking soda, 1 pound of either to 30,000 gallons of water.