1. Go to Walmart or equiv and get 16+ gallons of plain 8% bleach AND a cheap OTO / phenol red drops kit (HTH DPD goes to 5 ppm, and bleaches out somewhere between 10 and 20 ppm!)

2. Physically clean all algae piles and debris. Put pump on recirculate rather than filter.

3. Begin dosing your pool in 4 gallon increments. Retest with OTO after 4 hours of circulation. Repeat dose if chlorine level is less than DARK yellow. Continue this till pool goes from green to gray.

4. Brush the pool completely (even if you can't see!). Make sure the chlorine is DARK yellow before starting. Pool may go green again. Check chlorine after 2 hours -- repeat dose if not DARK yellow.

5. Hold chlorine high 24 hours after brushing. Allow chlorine to drop to 5 ppm. Add a SINGLE dose of whatever clarifer or liquid floc you have on hand. Circulate per instructions, or for 4 hours. Turn pump off overnight.

6. See if algae is going to settle. If it does, let it settle for 24 hours. Maintain chlorine via direct additions. Vacuum piles to waste.

7. Once you've vacuumed what you can OR if it's not settling, turn pump on and begin filtering. Wait at least a week before adding any more clarifier. Do NOT use a 2nd dose of floc.

8. Once you can see your pool returns, you can add a small amount (2 - 3 cups) of DE filter powder to a skimmer. If a cloud shoots out of a return, your filter needs work. If not, you can use repeated small doses of DE to help remove the algae . . . but it will force you to backwash much more frequently.


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How to avoid this? Ask after July 4th.