It’s funny that we never hear customers complain about phosphates being in their pool until their pool is green. Did you know that phosphates are always in your swimming pool, even when there are no algal blooms? That’s because it doesn’t cross your mind when your pool is nice and blue. After reading through various articles and customers’ questions on removing phosphates, I’ve come to one conclusion, there’s a lot of misconstrued and misconceptions regarding phosphates in your swimming pool. What exactly are phosphates? Where do they come from and how do phosphates get into your swimming pool? What is the threshold for phosphates before it becomes harmful to the swimmer?
Let’s explore phosphates a little more.
What Are Phosphates?
Phosphates are nutrients that help increase plant growth. Naturally, you can find phosphorus material all around. That is why it is common for phosphates to be in your swimming pool. But how exactly do phosphates enter your pool? There have been many debates suggesting how phosphates enter your swimming pool. Some argue that excess rainwater or fertilizer can affect your phosphate levels. Which is true, sort of.
How Do Phosphates Enter Your Swimming Pool?
Phosphates might enter your pool one of several ways, but rainwater is not one of them. Rainwater itself isn’t phosphorous. In fact, it’s impossible as phosphates do not atomize in the atmosphere. However, once the rainwater runs off into the soil, then it becomes phosphorous. Usually, swimmers bring the majority of the phosphates into the pool with them. Contaminants like makeup, lotions, shampoos, dirt, leaves, and other pool chemicals like scale and stain products account for the majority of the phosphates in your pool.
When and How You Remove Phosphates From Your Pool
Whenever you have an imbalanced pool, one of the first things you should do is test your water. Before you can remedy the issue, you first need to determine what the issue is, right? So what happens when the store clerk tells you your water has a high amount of phosphates? Naturally, the first thing pool owners do is go out and purchase a phosphate remover and add it into their pool.
If you’ve already experienced this, you already know that this won’t solve your green pool. Now, you have a green pool AND white sediment at the bottom of your pool. The first thing pool owners should focus on is removing the algae. In this particular case, once the pH and alkalinity levels were correct, the water was clear. To be honest, there probably wasn’t a need to purchase the phosphate remover. In most cases, you won’t have a need for phosphate remover.
In fact, there is no scientific evidence that even proves that phosphates actually increase algal growth rates when phosphate levels are below 1000 parts per billion (ppb). McGrayel Water Technologies completed a study and it was determined that algal growth rates are unaffected at each phosphate level. They also determined that phosphates are not likely to be a problem until after levels are above 1000 ppb.
Before adding phosphate remover into your pool, make sure you actually need it. We do not recommend adding unnecessary chemicals into your pool. Remove phosphates from your pool when levels exceed 1000 ppb. Once your phosphate levels exceed 1000 ppb, I would consider purchasing a phosphate remover. Keep in mind though, phosphate remover will not rid your green pool.
Reduce the high cost of removing phosphates by being proactive. Keep in mind, phosphate remover is preventative, not a remedy. Test and treat phosphates annually. There isn’t a need to worry about them constantly. Instead, focus more on keeping your pool properly balances.
i have been treating yellow algae for two weeks, using yellow out and the slam method on above ground pool algae still there. no trees around pool area. should I drain the pool and restart? its also equipped with salt water, Hayward equipment
After using a phosphate starver my cell shut down as the cartridge was clogged with a white gluey substance. Is this normal that the phosphate converts to a white glue that you can just hose out of the cartridge?
I have not heard of a white gluey substance in the filter stemming from the use of phosphate remover. It may be specific to the brand of chemical you used. If it is easily washed off the cartridge, then it shouldn’t be much of an issue. Did the instructions of your phosphate remover state to remove the cartridge or bypass the filter?
Informative article, even for a professional such as myself! The study you cited got my attention and prompted me to comment, since I had only ever heard ‘phosphates are always bad.’
Thanks for your contribution, and Hapoy New Year!
Great article!
We have a salt generator. This past spring I noticed that we could not hold chlorine in this pool for anything. I was shocking it every 2 days and the chlorine would be gone withim 24 hrs. I couldn’t understand what was going on. I thought the salt cell had gone bad in less than a year. Thankfully my husband does service and repair work for a pool company, and we were able to get a new cell without using our warranty. He does repair work and installation and does not have much experience with pool chemistry otherwise I probably would have figured this out sooner LOL! Anyways, new cell in place, and we blasted the pool with trichlor because we were treating for black algae too. Everything seemed to be pretty good for a few months.
Last week the same thing started happening. The pool was loaded with algae. I couldn’t keep chlorine in it. I would shock it and run a boost and 24 hours later there be nothing in it. I wasn’t going to go through this again. There was no way we had two bad cells.
I took the water down to have it tested. I told him what was going on. All of our chemicals were in perfect check. We had plenty of cyanuric acid. Our pH was 7.4. No chlorine though. They said this is probably a phosphate issue. They ran the tests and our phosphate levels were 1500. Way over the normal recommended limit. I bought the phosphate remover which was a little pricey. We spent the next 48 hours filtering out all the phosphates and residue. I think we washed the filter five or six times. That’s how much it was filtering out to the point it was so clogged that it would stop spilling over from the spa running at 2700 RPM. That is a severely clogged filter.
4 days into this, the pool looks fantastic. The algae is gone the chlorine levels are holding between 5 and 7. I’ve got the salt generator running back at 35%. After this experience, it would be my guess that the other cell was never bad and this was the problem. I have read articles stating that high phosphate levels will compromise the performance of a salt generator. There was one site that would not acknowledge that. They said there was no scientific data to prove it. Well I don’t need scientific data because I just went through it and that’s exactly what was going on. Summing it up, based on our experience, if your phosphate levels are high it definitely affects the way your salt generator performs.
Thank you for posting this article because you seem to be more willing to acknowledge that this is a real problem for people who owns salt generators.
We had a similar scenario this summer. It’s not that your salt cell went bad, necessary, it’s that after your filter clogs to a certain point, it inhibits the proper water flow (gpm) necessary to generate chlorine.
Our water wasn’t quite clear so I had the water tested. Our phosphates were around 2500 ppb. We treated it with Phosphate Remover and after 24-48 hours I noticed that the PSI had increased a fair amount and the SWG “no flow” light was on (which had never previously been a problem). I upped the RPMs on my VS pump until the “no flow” light turned off. The next day I backwashed and readjusted my RPMs back down.
In short, the phosphates themselves aren’t compromising SWG performance, it’s the low flow caused by a clogged filter (caused by adding phosphate remover in my case) that reduced the flow to a point where chlorine wasn’t being generated. No problems since.
They say my Phosphate level 1000, my pool is clear not green could this be a bad test or should i use phosphate remover. Also isn’t PH plus and Aklalinty Increaser baking soda, if i raise one of them will it take care of both problems.
Just because your phosphates are at 1000 it does not mean your pool is going to start turning green. If your pool is clear, then I wouldn’t worry too much about it. As long as you keep the chlorine levels in range, you will be fine.
Hello- soooo hoping you can help me. My phosphate levels aren’t 1100, they were 1600 but I used no phos and went down a bit but it’s still cloudy. Bought some pho’s Phix from another store and pool is still cloudy with billows of white particulate at bottom however I have a sand filter and have seen some of the particulate come back in through the jet. If I backwash and vacuum to backwash because I have to waste setting can I remove all this from my pool? If I can get it clear and below what phosphate level if I SUPER shock like I was told at one pool store to do with 10 lbs of shock to break a chlorine lock will this help restore my pool or am I better off draining and Getting a different type of filter
Phosphate levels are at 100 sorry
1100
If the white particulates are dead algae or some other materials, use a clarifier or better yet a flocculant to capture it and send it to waste. If sand or debris is coming through your return jets, it seems like you have a sand filter issue, like a broken lateral.
As the article says, remove phosphates from your pool when levels exceed 1000 ppb. But I believe you are focusing too much on the phosphates. If your chlorine levels are right, algae can’t grow, but this does not mean you need to scorch your water with a mountain of shock. Whatever place to throw in 10 pounds of shock to clear up some cloudiness, stop going there.
Got mine down to a count of 100, down from almost 4000 count. Used phosphate remover took 5 bottles. Restocked the pool. Gonna wait two days then have retest done.
I was told that phosphates are steroids for allergy…so you really don’t want any at all in your pool
Yes they very much so are!
For someone with a known specific allergy, it certainly can be. Common seasonal allergies are unlikely to be affected. Besides, the level of 1000 ppb translates to one part per million, which is detectable, but rarely a problem; consider this in light of the fact that a BAC of 0.01% concerts to 100ppm.
Hope that was helpful!
Not only does it exasterbate allergies but pollen in itself IS a phosphate. So there’s that.
Same problem as others…2000 – got rid of algae – added remover – shocked it twice – can’t get a free chlorine reading – add clarifier – water is pretty blue but cloudy – starting to think draining the pool is cheaper…….
My phosphate level was 1000 and I was told to add PhosFight. My water was crystal clear before and all chems were balanced. After adding the phosfight, it’s cloudy. Instructions say to run filter for 24-48 hours then backwash. Is it normal for this stuff to make the pool cloudy?
Yes, it will make the pool cloudy
How did you get rid of the cloudiness? I am having the same problem.
I just bought phosphate remover. We are gonna try the remover first. I went through all the forums and made a bunch of phone calls. Got alot of different answers but the most common answer was to treat the phosphate issue. Then introduce chlorine back into the pool. Please keep us informed.
I hope everything went well in the summer of 2018. As a professional in CA, where there is a huge pool industry base, I can validate the information in the article, and say that in the future, balancing the water ( Chlorine, pH, and Cyanurate level), which the article recommends, should always be the first step in correcting any water quality issues, esp. with problems like algae or staining. Balancing the water then physically brushing the algae will almost always correct the issue in the short-term. The exception to this is if there is high TDS or a non-soluble suspended in the water.
Once the water is balanced and the algae no longer visible, that is the proper point to test phosphates and use a removal product.
Hope that helps, and wishing you good gortune and fun summers!
Phosphates down to 2400 after second treatment. Water still is crystal clear. I am getting conflicting opinions on whether it is necessary to treat these phosphates. My biggest concern is I can’t keep a chlorine reading in my water. One pool supply store is recommending we drain significant amount of water and at noon and the other is saying don’t worry about it just do what we would normally would do with chlorine and pH as long as the water still clear. It has been almost a week since we have been able to treat it with chlorine with the 85° weather at this point I need to worry about algae. Thougjts? where do I go from here?
Shock the crap out of it. That’s what we had to do in order to get our to register. I initially did 3 bags of shock and algaecide to open the pool (whoops you don’t use both within 24 hours) and it turned blue but super cloudy…. Shocked it again with another 3 bags, nothing. Added cya stabalizer to the min required levels….. Added SIX yes SIX bags of shock, and we finally get our chlorine up. Then still to my surprise very very cloudy but blue. Everything was balanced, took water to the pool store and phosphates were at 3600… So now we’re working on that…. And now the pH went down and all went up 🤷 I don’t even know anymore but I know we have chlorine in the pool now.
We are having exactly the same problem as Laurie. Took a water test today to pool place and said our phosphate was extremely high. We have shocked our pool 5 nights in a row and every morning there test say no free chlorine using test strips and by having water checked. Going to buy phosphate remover today. Looking for good product. Any help be appreciated.
Swimables phosphate remove x is what I just purchased. Out levels were at 3600 for a 13,000 gallon pool. If one bottle of phosfree spring and fall only clears 300ppb for 25,000 gallons that means about 600ppb for our pool…. That’s ALOT of phosfree or buy at $20 a bottle. I got a liter of swimables remover x for $32 and it’s concentrated to uses less product to remove more ppb. Hope it does the trick. I’m not going to have my water tested until 48 hours… It’s stressing me out
We get results tomorrow. prIor to the first phosfree treatment we had used flock and clarifier As I mentioned pool water is crystal clear our biggest problem is being able to keep chlorine in the water That is why we had the water tested and they found it was high and phosphates They indicated that the phosphates eating the chlorine that is why we could not keep chlorine in the pool
Try looking up chlorine demand and taking corrective action as outlined
The product did not require that I bypass the filter. it stated to pour in the skimmer and run for 48 hours and then backwash. we are on our second treatment. We don’t know what to do next
What were the results after your second treatment? have you used a clarifier or floc in combination with the phosphate remover?
My water is crystal clear. Phosphate at 2450 after one treatment of phosfree. Was at 2550. Only dropped 100 after first treatment. Chlorine is now gone. Our second treatment is in process. Should we see our pressure on a sand filter increase? We did not our first treatment and the pool supply store was shocked. We have a sand filter. This is our second year with it.
After the treatment, did you backwash and rinse your filter? Also, some phosphate agents require that you bypass the filter media, by setting the multiport valve to recirculate. This is because those phosphate agents clog the filter. Did your instructions have this step?
Yes we backwashed after the firat treatment The pressure never changed with the first treatmen. We back washed after the first treatment and have a sample tested again It only went down by 100.
My questions are: 1- SHould my sand filter build pressure? 2 – is it noRmal to have the water be crystal clear with high levels of phosphates?
As stated in my previous response, if you used a product that required you to bypass the filter media but you did not do so it could cause clumping and clogging.
Yes, you can have clear water with high phosphates.
Hi, I had phosphate level at 1300 so my pool company told me to get commercial phosphate remover. It worked. I just poured in pool like he told me to and I feel like I have to backwash a lot cause my flow light keeps coming on???
The flow light on what piece of equipment, a heater, salt system, VS motor control? That is important to know, to be able to determine how to fix it.
Is there a chemical compound substitute that I can use instead of the expensive PhosFree products..Example, I use soda ash to raise the PH,,can buy in bulk very cheap.
Thanks
I have not found a home remedy phosphate remover yet. Still on the look hour for one.
I ve had my pool running since May 19th 24/7. First it was the usual alkalilne ,ph, shock. The it was metal remiver, followed by iron remover, tons of schock, and liquid shock , then finally phosphate remover, Not once but twice . My pool is cloudy cannot see the lunar net it hittom at all . Phosfate reading 4699. What can be done ?
Stain removers and metal sequestrants can cause a spike in phosphates. Since you added so much metal remover, you probably have to re-dose phosphate remover.
We have given up and drained the pool to start over. What will we do with many buckets of phosphates that we will have to scoop out of the bottom?
A garbage bag would be a good solution. Pour down storm drain if they will let you do so in your area.
Hello
I’m having a phosphate problem for the first time this year. My phosphates were tested to be approx. 4600 ppb. After treating with commercial grade Phosfree and the highest strength phosphate reducer it is still testing at 4000 to 5000 ppb. Is there anything left that I can try besides emptying the pool and refilling?
Thanks in advance for you help
I would go with another treatment of the phosphate remover. Maybe try a different band.
When draining the pool, I wouldn’t drain the pool completely, just like a third or a half.
It took me 5 treatments to go from 2000+ to zero, and takes attention to keep it below 500. Suspect organic crud through the screen from surrounding trees as the cause. No need to renew water. Once you get it to 500, weekly/2-weekly phosfree treatment should maintain it without cleaning the filter every time.
Biodex phosphate remover plus, it’s expensive but the best chemical I’ve come across. Dropped ppb by 2000 overnight
Hi
I live in Phoenix with current temps around 110.I also have many trees around my pool that shed debris into my pool. My phosphates are reading at 500ppm. Also my Chlorine is reading high right now. I purchased POSfree per the recommendation of the pool supply store. When I was reading the label it states.
Important- Do no test Phosphates if the Chlorine is high. My question is, should I go ahead with using the Phosphate remover?
Thank you
Does it say not to test for or not to use the phosphate remover while the chlorine is high?
Yes it says do not treat with phosfree if the chlorine is above 5. This year upon opening our pool no debris was in it but it was an unslightly dark green. We shocked, did algaecide last Tuesday and it was left cloudy with no chlorine registering we shocked again after everything else was balanced and the chlorine went sky high. Been cleaning out filter cartridge (two new ones swapping out) and still cloudy you can maybe see a foot down into the water but it’s blue. Tested the water today and phos was at 3600! I used the whole bottle of phos free as suggested and you are to wait 48 hours with pump running and then rinse your filter. My alk which was slightly low when tested at the pool place is now sky high and the pH fell down. I’m not even going to attempt to mess with anything or retest until 48 hours now. I’ve never had this much trouble. Lesson learned buy a better pool cover this fall…..
Great article. I appreciate what you do with this site. Very informative. My pool turned a cloudy green over the span of 3-4 days. I’ve cleaned my filter cartridges and took my water into our local pool store to have it tested. The chlorine and pH levels are in line and actually a little high. However the phosphates are at 1000. So try suggested adding calcium to lower the phosphate levels.
Sounds like this won’t necessarily clear up the pool so I’m not sure what’s happening to the pool. The only recent event I can think of is we recently turned on a pump for a waterfall in the pool and noticed the water in the pool pump was very green. Could that have circulated algae into the pool which then started feasting on all the phosphates?
It doesn’t matter how many phosphates are in a pool, if chlorine is present in a sufficient enough number algae cannot live. Take a look at our how to clean a green pool article and video. I’m not sure where the algae came from, but if there is cloudiness, then your chlorine is working. Cloudiness after an algae bloom is a sign the algae is dying. Add shock and algaecide, to expedite the process. Keep your chlorine levels elevated, until the green is gone. Add clarifier to clear the cloudiness after the green is gone.
But it does matter how much phosphates are in the water, doesn’t it? The first year we had our pool we never had a problem, 2nd year it turned green once and the 3rd year (last year) it turned green like 6 times at least – every time we kill the algae dead algae makes mor phosphates which feeds new algae. I do agree with not putting unecessary chems in it though because it seemed like the more the pool store told us to put in our pool the worse it got… however I feel like if we had cleard the phosphates after an algae bloom was killed it might have helped us avoid the next which usually came within a week of the last.
The long and short of it is, if you maintain proper chlorine levels, algae won’t grow. Phosphates are food for algae, but algae can’t eat if it’s dead. An easy way new pool owners get behind on chlorine production is not keeping your CYA in check, which inhibits the chlorine if the CYA levels are high. The water turns green even though you’re adding the same amount of chlorine tablets, but you are not accounting for the higher levels of stabilizer. This might explain your algae issue got progressively worse and worse.
My phosphates are like 3700….and can’t get them down!! And have been fighting mustard algea…
Make sure you are cleaning the filter. You must use a phosphate remover and then clean the filter a day or so later. My levels went down only after rinsing off the cartridge filter.
MINE ARE 3800 I USED 100 + OZ. LESLIE’S NO PHOS 2 TREATMENTS THEY WERE 4800 WHEN I STARTED! WATER IS CLEAR AT $ 58.00 A BOTTLE I’D LIKE A CHEAPER WAY TO GET THEM DOWN….
Draining a portion of your pool water will remove phosphates. That is a pretty cheap solution.
Me too☹️
I had my water tested and it was over a 1000.My water was a light green.I just added the remover today.I noticed some stuff on the bottom few hours later.Just wondering what i am to do after.All other levels are normal.I need the green gone
The green is algae, and you need to concentrate on getting rid of that first. That will involve a bunch of shock, algaecide, and backwashing. Take a look at this: How to Clean a Green Pool?
I’m fighting the phosphate battle right now. This is helpful. Had my water tested for phosphates. Came back really high. This is the first time EVER I’ve had this problem. The only thing I can attribute it to is that a high wind storm partially took off our [water bag] cover in the spring. Lots of yuck that was on top the cover mad its way into the pool water.
Took my water into Leslie’s Pool They said phosphates are high , They said to drain half the water out and put fresh water in there is no algae in my pool that I could see but it’s a little milky what should I do and can the kids swim in it it seems like the chemicals are pretty close to being balanced
Be careful of Leslie’s Pool. They said my phosphates were high (200 ppb – not high at all!) and sold me a $60 bottle of their “Perfect Weekly” which doesn’t even say what the ingredients are, or how much to add. It seems to be some kind of enzymatic additive with maybe a surfactant to slow evaporation, but I have a pool cover for that. I plan to return this stuff and look elsewhere for pool supplies. I have enough people trying to sell me “snake oil” as it is. I’m all for supporting “brick and mortar retail” that provides a service but I don’t care to be ripped off by them either.
Thank you for your story, Bruce. In my earlier days, I’ve been upsold on the fancy new chemical of the month. I’ve learned that if a salesman brings up a brand new product that is “guaranteed” to fix my issue, I do my research before pulling the trigger. Chances are, it usually is some kind of basic enzyme cleaner that is just a general clarifier or sequestrant.
As long as the chlorine levels are not over 5ppm, you should be good to swim. Is the water milky due to the chemical treatment or do you believe it is because of the phosphates?
Great information!! This site has given me a lot of knowledge about owning a pool. Many problems have been solved just reading the info posted in the email messages with the links to the articles. Keep up the great work!!!
Thanks, Tom!
Hi my phosphate are very high I have treated it with the phos free when I back washed it the first time looked like rusty dark brown water. Treated as directed with back washing and all. Now the water is beautiful but it’s still testing off the chart for phosphate. What now? Never ever had a problem with This before
If the water is beautiful then it doesn’t seem like you have anything to worry about. As I have said countless times in this comment thread, if the chlorine level is kept in the proper range algae cannot grow.
Phosphates are food for algae, not the cause of it. Chlorine kills/prevents algae before it can gobble up any tasty phosphates.
Thank you so much for this info. We are ne owners to a 30k gunite saltwater pool. The local pool store keeps telling us to lower phosphatase due to them being over 4000! The pool is beautiful and all other thing are in perfect balance. We have spent hundreds of dollars on their products that aren’t bringing the phosphates down. Every time we treat the pool looks Murky and grey settlement all over. If we can ever get it clear I think I will just do some algae guard and call it good.
Very helpful article! All my pool water samples in the summer were balanced except for slight problems with pH being too high, which we would treat with muriatic acid or pH Down. The phos always hovered right below the 500 which was noted as the “high normal “standard. I always worried about it but no more!! Knowing that 1000 is the limit helps a new pool owner! Looking forward to late spring 2018!!!!
Thank you!