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How to get rid of phosphates

Why phosphate levels matter? Lets look at the impact on pool algae.

If you can control the availability of Phosphorus, you can somewhat control the algae growth.

The first thing you need to understand about pool water chemistry is that the whole point here is that we are trying to create a safe water environment for our swimmers.  We need to keep algae and bacteria out of the water.

The thing with algae though, in the right conditions it can grow and thrive in your pool.  Algae needs sunlight, some kind of carbon, nitrogen and phosphorus to be able to grow.  Out of all of these needs, it’s the phosphorus that is less available.  Everything else seems more readily available, but if you can control the availability of Phosphorus, you can somewhat control the algae growth.

How do phosphates affect my pool?

In most pools people don’t care about phosphorus and they rather tend to control the algae by using chlorine or another sanitizer.  Whilst this works well, and will stop the algae and bacteria from growing, the moment these chlorine levels lower, if there is sufficient phosphorus in the pool, the algae will grow quickly.  In effect, if you can starve the water from phosphorus, you are creating an inhospitable environment for the algae to grow.

Whilst the first step it to maintain a sufficient level of free chlorine in the pool to kill any algae, eliminating phosphorus from the pool will make it much harder for the algae to grow, even when the chlorine levels dip.

Green pool with phosphates
Phosphates will feed Algae

What to do if I have high phosphate levels?

So if you have high levels of phosphate in your water, the next step is to use a phosphate remover. Phosphate removers are a chemical that contains lanthanum chloride. This reacts with the dissolved phosphates in the water and makes it into a solid form.  It will find the phosphates in the water and combine with it, to create a solid state. In this solid state your filter can now capture it and rid it from your pool.

What if my pool is already green?

Remember that once algae and bacteria are growing in your pool, they have already consumed some of the phosphates and bound it up, so the lanthanum chloride can’t actually access the phosphate and react with it.  So it’s more of a preventative method, rather than a treatment of algae.  If you have algae already it’s important to shock treat the pool and get rid of the algae and then treat the water with a phosphate starver.

For more information, or for help with your pool, please contact us today for a pool service.

Poolzone 0432 105 352


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