Nitrates and Phosphates in Pools
The process of introducing Nitrates and Phosphates into our swimming pools is called eutrophication.
Phosphates and Nitrates are the main reasons we get repeated algae-blooms in swimming pools. In South West Florida, we get large amounts of rain from May thru October. These rains ‘along with Phosphates and Nitrates is the major force in yellow and green algae blooms in pools.
The most likely form of Nitrate and Phosphate contamination in our swimming pools is from wind -blown fertilizers. This fertilizer can come from several of your neighbor’s yards, not just yours. Decaying plant materials, animal waste, acid rain and reclaimed water come in a close second. Make sure your sprinkler water does not blow into the pool.
Testing: We can test for both Phosphates and nitrates. Phosphates can be removed by adding chemicals. Nitrates can only be diluted with a water change.
Treatment: once you have had two or more algae outbreaks within a two month period, you will need to
- Maintain PH 7.4 -7.6
- Maintain Alkalinity at 125 -150ppm
- Maintain Chlorine levels at 4 -6 ppm
- Shock pool
- Advise swimmers to shower before entering pool.