​Phosphates are naturally occurring minerals that can come from fertilizers, lawn sprays dying plants, mineral treatment chemicals, bird droppings, groundwater runoff and even dead skin cells (so, they can come from a whole list of places.)

They cause trouble in pool water sometimes because they act like food for algae, which, if left untreated, can create a big algae problem.  Now, there happens to be a debate out there in the cyberspace pool community as to whether or not phosphates are that big of a problem, and if they are a problem, what is the level that they become a problem at.  Is is 100 ppb (parts per billion) or is 1000 ppb?  Well, my feeling is if you are having a hard time keeping your chlorine levels up and your phosphate levels are on the high side, you should try a phosphate remover.  Using a weekly dose of phosphate remover, along with maintaining your chlorine levels and keeping the rest of your water in balance will probably be cheaper in the long run than having to try and clean up a huge algae problem.

Another item to considering the debate about phosphates is our climate.  We live in the desert, and the temperatures reach well into the 100's and stay that way for weeks at a time and the kids all pile in the pool for hours on end. This is murder on any chlorine residual and makes it hard to keep the levels up, whether you are using a salt chlorine generator or an inline 3-inch tablet feeder, both will be taxed.  When you add phosphates (which are a plant...read algae...nutrient) to a pool that is struggling to keep sanitized, it can make it even harder to keep the chlorine up.  The phosphates then feed any algae problem and make it worse, and then the algae starts to eat even more chlorine.

You can add chemicals to remove some of the phosphates from your water, such as Bio-Dex Phosphate Remover, Bio-Dex Phosphate Remover Plus, or Natural Chemistry Phos Free.  Since the phosphates are what the algae feeds on, removal of the phosphates will remove the algae because it won't have anything to eat.