Pollen from pine trees surrounding your pool can lead to a messy situation in late spring and summer. The pollen clings to the edges of the pool and, if you have multiple pine trees in the area, could turn the water yellow or green. Green algae sometimes masks as pollen but is usually a darker green colour and slimy, so before you start treating the pool, make sure pollen is the problem.
Turn your filter on and keep it running 24 hours a day when pollen is a problem. A running filter alone should take care of most of the pollen in your pool. Regularly backwash the filter and check the psi on the gauge. When the psi is 10 more than its base level, it is time to backwash again.
Add clarifier to the water if you have a sand filter. This will bunch together the pollen particles, making them easier to remove. Be sure to check the label for types of filters that will work with the specific clarifier. Wait a few hours, allowing the chemical to work.
Skim the pool, placing a fine mesh insert into your skimmer to catch the smaller particles. Once you remove the coagulated pollen from the top, you will be able to see into the pool more clearly.
Vacuum any pollen on the bottom and sides of the pool. This combined with skimming will decrease the amount of work the filter has to do.
Repeat steps until the pool is clear. This can take time, especially if you have multiple pine trees dropping a lot of pollen.