Bleach Removal

• Algae are microscopic plant forms of various colors that can contaminate a pool almost overnight. When using bleach to remove pool algae, know that it takes about a gallon to raise a 30,000 gallon pool's chlorine level to 2 parts per million (ppm). Therefore, anywhere from 5 to more than 12 gallons of bleach are required to adequately sanitize an algae-contaminated swimming pool. Also, using bleach in a swimming pool to eliminate algae presents several special issues to understand.
  
  

Bleach pH

• Standard household liquid bleach has a high pH that runs from 10 to 16 while swimming pool pH should be between 7.2 to 7.6. Adding bleach to a swimming pool to remove algae also means that you'll raise the pool's pH up past 7.6 at least. Be aware that after superchlorinating your pool with bleach, you'll also need to lower its pH levels. Ensuring optimal swimming pool pH has a direct effect on continuing pool chlorine effectiveness after superchlorinating.
  
  

Light Sensitivity

• The chlorine in bleach is sensitive to bright light as all chlorine is. Outdoor swimming pools are made to bask under a lot of sunlight, so any chlorine bleach added is at higher risk of dissipation due to that sunlight. To give the chlorine in bleach every opportunity to remove algae from a pool, help it avoid sunlight, or to strengthen chlorine's effectiveness, only shock or superchlorinate a swimming pool at dusk or in the evening.
  
  

Superchlorination

• Depending on how heavily contaminated a swimming pool is, 10 to 25 ppm of pool chlorine is required to kill off all algae. Add chlorine bleach to a pool slowly, and ensure it's spread widely throughout the pool. You can add bleach through the swimming pool's skimmer unit, if desired, which would allow the filtration unit to spread it all over the pool. Frequently a couple of bleach superchlorination treatments are necessary to fully eliminate pool algae.
  
  

Water Chemistry

• Using any form of chlorine, including the chlorine in bleach, to remove swimming pool algae will throw off a pool's water chemistry. At minimum, after superchlorinating with bleach to eliminate pool algae, you'll need to lower your pool's pH and stabilize its chlorine levels. The most common chemical used to lower pool pH is muriatic acid (MA) while cyanuric acid (CYA) is used to stabilize chlorine. Add both MA and CYA to a swimming pool strictly in accordance with each acid's package instructions.