What are Phosphates?

Many London, ON pool-owners struggle to maintain the clarity of their water.

Due to a mild winter, without a ‘hard freeze,’ algae has much more time and freedom to grow. With such a difficult struggle, it’s no surprise that pool owners are looking for something to blame. For some people, the scapegoat became phosphates.

Are phosphates truly the root of your issue? The answer is: ‘possibly.’ Here’s what you should probably know…

Phosphates are food for algae. With lots of food, algae can grow more quickly and will be more resistant to methods for removing it.

In pools that are properly maintained (consistent sanitizer, pH, and proper water chemistry), phosphates are rarely an issue.

When a pool is maintained poorly, phosphates can make the fight against algae much more difficult.

The take-away here is that your pool may be very well-maintained during the season, but very few pools open at the beginning of the season in ‘great’ or ‘well-maintained’ condition. As a result, you are faced at the beginning of the season with many of the problems that plague a poorly-maintained pool, including phosphate levels.

When algae is already abundant, having high phosphates can make removing that algae much more difficult. Some people see almost no response to chlorine with phosphate levels over 2000. In such cases, removing the phosphates will make removing the algae much more manageable.

To be clear, removing the phosphates will not necessarily remove the algae. The sanitizer (chlorine, for example) will still be needed for that part. However, with the algae food less available, the algae will die much more quickly in the presence of chlorine.

You should not necessarily need to worry about removing the phosphates in your water if the water is already clear and/or algae-free. You are unlikely to notice much of a difference in your regular pool maintenance whether your algae is high or low (assuming that you maintain your water chemistry appropriately).