Individuals with normal color vision will see a number, while those with a deficiency do not see it. On some plates, a person with normal color vision may see one number, while a person with a deficiency sees a different number.
Your phosphate level should be at or below 100 parts per billion (ppb). If your water chemistry and phosphate levels seem to be in check, one potential cause of the cloudiness in your pool could be dead algae. Phosphates are the food supply for algae, thus high phosphate levels promote algae growth.
There are three typical biological growths found in cooling water, algae, bacteria, and fungi. The different varieties of algae are unique among the three forms in that they make their own food. This is done with the use of a green pigment called chlorophyll that is found in algae.