ORTHO-PHOSPHATES (which this kit measures) are the limiting nutrient for algae growth. Without phosphates algae cannot grow, so controlling phosphates in a pool is very important. Phosphates occur everywhere in the environment. Sources include; runoff, leaves, vegetation, fertilizers, rain, dust, people, animals, and many other sources.

Fortunately, phosphates can be easily controlled by:

Testing frequently, especially in the spring and fall to monitor phosphate levels.
Removing phosphates (depending on range) and keeping phosphates below 100 ppb.
Use Pool Perfect+PHOSfree weekly following label instructions to maintain phosphate levels near zero.
 

Phosphate test kit for professional use,
2 Vial Containers with 50 strips per vial plus one test tube.

4-in-1 OTO blue test kit, chlorine, bromine, pH, alkalinity, acid demand-

4-in-1 DPD red test kit, free and total chlorine, bromine, pH,
alkalinity and acid demand

Solution #1-OTO / 1 oz bottle

Solution #1-OTO / 8 oz bottle

Solution #2-Phenol Red / 1 oz bottle

Solution #2 -Phenol Red/ 8 oz bottle

Solution #3-Acid Demand / 1oz bottle

Solution #4-Chlorine Neutralizer / 1/2 oz bottle

Solution #5-Alkalinity Indicator / 1/2 oz bottle

Solution #6 -Water Hardness / 1 oz bottle

Solution #7 / 1/2 oz bottle

DPD #3 tablets / box of 250

4-in 1 test block

4-in 1 plus DPD test block