The quick answer to this question is, yes! We absolutely need phosphate removers for winter. In fact, we’d go as far as to say that it is actually one of the most important things to add to your pool just before closing it up for the season.

Phosphates usually come from body waste (we see phosphate levels spike up after heavy pool usage) as well as from any dirt, debris, leaves, bugs, and other stuff that falls into our pool.

Why are Phosphates an Issue?

Phosphates are basically phosphorous molecules that are bonded to oxygen molecules. Why is this important for us to know? Phosphorous is basically plant food, and algae are just simplified versions of plants with the one goal: and that is to reproduce as much as possible. Phosphate levels do not go down by themselves, the only time that phosphates go down is when they are removed with a chemical or when they are consumed by algae. So what basically happens is that when we have high phosphate levels, algae has more food so they grow faster which drives up the demand for chlorine in our pool, making it harder for our pool chlorine to catch up and prevent algae blooms.

Why do we need to remove phosphates?

If algae are constantly eating phosphates then why do we need to remove them right? Well, the simple answer to that is it’s much more cost-effective to deal with the phosphates themselves. All it takes is an application of phosphate remover to clear your pool of phosphates. On the other hand, if we just leave them there and think “oh, they’re getting eaten by algae anyways, I’ll just continue to add chlorine” then you’re putting your pool at risk!

The easiest way to explain it is this way. The more food algae have, the faster it grows. The faster algae grow, the more chlorine demand there is, the faster your free chlorine levels will drop. The faster your free chlorine drops, the more openings algae have to grow and bloom out of control. Now, after seeing that, would you really want to risk a full-blown algae bloom?

Even if you don’t get an algae bloom, you would still end up adding a lot more chlorine than you usually just to catch up with the chlorine demand. More chlorine added means more expenses on your part. And forgetting or skipping just one dose can again turn your pool into a swampy green mess overnight!

How to get rid of phosphates?

There’s one way to get rid of phosphates and that’s to use a phosphate remover for your pool. Now, many standard test kits do not include phosphates as a part of the tests involved so if you want to be absolutely sure that you need to add phosphate remover then you may need to buy a specialized test kit or take a water sample down to your local pool shop.

How often do we need to take out phosphates?

Here’s a little bit of good news for everyone. Phosphate levels do not jump up overnight. Depending on your pool usage and exposure to debris, phosphate levels can sometimes take months and even years to build up to levels where they become an unlimited food supply for algae to feed on. In fact, if you think about it, the best time to remove phosphates is right before we close our pool for the season. Why is this? Well, if we think about it, for the whole year we’ve been steadily adding phosphates to our pool with usage and from all the debris going in and out of our pool. It would make sense to remove all of the accumulated phosphates at the end of the season so that we can start fresh the next season.

Why not remove it when we open the pool? Why add phosphate remover as we close it for the winter? As we have explained earlier, phosphate is basically algae food. We really don’t want algae to have an all-you-can-eat buffet with them under the covers during winter right? Especially when we can’t keep a close eye on our pool!


Phosphates are very easy to remove, take a bottle of phosphate remover, follow the dosage instructions on the label, and that's it! You've rid your pool of unwanted algae superfood. We also recommend using a long-life algaecide in tandem with phosphate removers so that not only will you starve out whatever algae there is in your pool, you're also killing them! This ensures that you pool remains algae-free even if there are lapses in your chlorine balancing!

Do you have any questions about this topic or the featured products? No worries, we're here to help! Drop us a question down below and we'll get back to you ASAP.

Happy swimming :)

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