Natural Chemistry's PHOSfloc Phosphate Remover is perfect for reducing the phosphate to a manageable level in pools with a high phosphate level (1,200ppb or higher). Additionally, PHOSfloc Phosphate Remover is environmentally friendly and non toxic. Before using PHOSfloc, the water's pH level must be adjusted between 7.0-7.2. Add the necessary amount of PHOSfloc to water and mix. A 20,000 gallon pool needs 2-4 lbs, the product will not floc properly if an insufficient amount is added. If your pool has a re circulation (filter bypass) setting, add the PHOSfloc mixture slowly to the skimmer and allow it to circulate for an hour. Do not add directly to the filter. Then turn your system off and allow PHOSfloc to settle, it may take 12 hours to do so. Once done, vacuum sediment to waste. If you have no re circulation setting, add 4 lbs of PHOSfloc to a large bucket of water and mix. With the filter off, add the mixture to the pool while walking around it. Allow the product to settle, then vacuum sediment to waste. Afterwards, use PHOSfree to reduce phosphate levels near zero. For more info contact the pros at PoguePoolSpa.com.