Phosphates, Nitrates, and algae

Phosphates and nitrates are food for algae. Both of these enter your swimming pool via debris like leaves, dirt, grass clippings, palm tree flowers, dog hair, etc.
It can be expensive to remove Phosphates, so the best way to handle them is
to avoid them in the first place. The best way to avoid these is to keep your trees and bushes trimmed and make sure when it rains there is no dirt washing into the pool. Also you will want to empty your skimmer basket and leaf catcher (if present) regularly if you have a lot of trees around your pool

In the temecula valley our biggest source for these are palm tree flowers, so keep your trees trimmed and save that money!

NitrateS

Phosphates can be removed chemically, however Nitrates can only be removed along with the water

For more info about nitrates in your pool CLICK HERE.
to see what the World Health Organization has to say about nitrates CLICK HERE.