Phosphates.....are they worth removing??

[Saturn94]

Discussion is absolutely fine. Converting inconclusive discussions into TFP policy or advice dilutes our mission. We are a teaching forum dedicated to help everyday folks solve their everyday pool problems.

Far too often, we have too much "parroting" on this forum wherein responders suggest something they have read here but do not understand the complexity or the caveats of the subject.

"Why don't you try phosphate remover?" may make a responder feel helpful but for the OP starting a SLAM, it is only inserts confusion and does nothing to help OP clear his pool.

So, certainly, reasonable things can be discussed here just like we are doing. That said, don't think that discussions like these don't work their way out into mainstream advice without regard to the many many qualifiers that need to be considered.

Thanks for the clarification.

 

[ajw22]

The Taylor test tops out at 1000, so it’s at least that, but I suspect it’s much higher. I haven’t tried a dilution test to see if I can pin down a number.

The Taylor K-1106 can do 2 different phosphate tests. One for 0-1000 ppm and one for 0 - 6000 ppm. It comes with two different comparator cards.

Phosphate Test Kit, 0-≥1000 or 0-6000 ppb

 

[Leebo]

Far too often, we have too much "parroting" on this forum wherein responders suggest something they have read here but do not understand the complexity or the caveats of the subject.

"Why don't you try phosphate remover?" may make a responder feel helpful but for the OP starting a SLAM, it is only inserts confusion and does nothing to help OP clear his pool.

This is actually one thing that keeps irking myself as well. Often I see users enter TFP saying they went to the local pool store with a green pool and were told they must remove phosphates to clear their pool. This is hogwash. If anybody does wish to parrot info from this thread to newbs with a green pool, please parrot the following info,

For starters we all agree a user should always test and dose accordingly. Don’t just dump in a ton of product hoping to cure your problems. Test using your personal kit, then add the amount of phosphate remover you need.....if any. So let’s now look at the user who has a green pool, well phosphate tests can toss a false reading when algae is in the water. You can see that from this photo of the Orenda K10,000. Under the instructions there’s this quote,

Be aware phosphate testing is subjective and is influenced by existing algae. Algae in a pool will result in a false reading.

Ya got algae, you’re likely gonna get a false reading for phosphates. Forget trying to remove them and focus on chlorine.

Second off, if you’ve got algae you’ll also have phosphates every time. The algae holds the phosphates in their cell walls and once the chlorine kills the algae the phosphates are released. If you use a phosphate remover before killing algae you’ll find yourself with a noticeable increase after all the algae is dead. First kill the algae by preforming a SLAM Process THEN learn about phosphates if you’re still interested.

If you have existing algae in your pool, a lack of chlorine was your problem.

 

[Saturn94]

The Taylor K-1106 can do 2 different phosphate tests. One for 0-1000 ppm and one for 0 - 6000 ppm. It comes with two different comparator cards.

Phosphate Test Kit, 0-≥1000 or 0-6000 ppb

Apparently, the kit has changed since I bought mine. I double checked and my K-1106 only came with the 0-1000 card. And unlike the one you linked, mine only mentions 0-1000 on the box.

I thought I read I can dilute with distilled water to do a dilution test, kind of like you do with CYA over 100. Is this correct?

 

[ajw22]

Apparently, the kit has changed since I bought mine. I double checked and my K-1106 only came with the 0-1000 card. And unlike the one you linked, mine only mentions 0-1000 on the box.

I thought I read I can dilute with distilled water to do a dilution test, kind of like you do with CYA over 100. Is this correct?

You can download the 0-6000 card from here https://www.taylortechnologies.com/Image/GetDocument/en/1218/5435.pdf It may be able to be used in your kit.

All of the documents for the kit can be found on the page if you click More Info then Documents

I think dilution is inaccurate enough to make any results questionable.

 

[bdavis466]

Phosphate removers are expensive... here's my technique to remove phosphates and CYA. Now all I feed my pool are pucks!

 

[Pool_Medic]

First, years ago this site would jump all over anyone posting nonsense about phosphate removers, pucks, algaecide and metal sequestrants. Now it’s taken a softer look and is in fact more friendly toward open dialogue over newer information. This is what this forum is about imo, letting people make their own informed decisions on how to run “their” pool, pool stores(who we all agree deals in false and misleading information) were the main reason the members took to google to find out better, cheaper ways. The phosphate remover discussion is for users who are delving deeper into ways to insure their pool runs crystal clear all summer. Not everyone is interested in daily testing to know their daily chlorine levels. Phosphate remover is one more insurance policy against a sudden bloom happening on a Friday before a sunny hot long weekend.

 

[duraleigh]

I saw a few articles where both nitrates and phosphates were listed as a food source for algae but none of them definitively said if algae prefers one or the other. If phosphates were REQUIRED, I assume that would be mentioned but I couldn't find that.

 

[mas985]

I saw a few articles where both nitrates and phosphates were listed as a food source for algae but none of them definitively said if algae prefers one or the other. If phosphates were REQUIRED, I assume that would be mentioned but I couldn't find that.

Both Phosphates and Nitrates are limiting agents meaning both affect growth rate. However, without phosphates, algae will not grow.

This article references the limiting aspects of phosphates:

Algal Growth - an overview | ScienceDirect Topics

www.sciencedirect.com

3.4 Phosphate removal
Of the nutrients that are capable of supporting luxuriant growths of algae in a receiving water, phosphorus is rate limiting, and a concentration of 10 μg/l is required before algal growth will occur. It has been argued, therefore, that control over phosphorus-containing compounds in aquatic ecosystems presents a means of controlling the deleterious effects of eutrophication. Consequently, if the small concentration of phosphorus that is present in sewage effluents can be removed, then algae will not be able to flourish, regardless of the nitrogen concentration. Phosphorus load control has been demonstrated as one of the most effective ways of dealing with cultural eutrophication. A typical phosphorus standard is 1 mg/l dissolved orthophosphate (as phosphorus). The major sources of phosphorus in domestic wastewaters are from human excreta (50-65%) and synthetic detergents (30-50%) and typical concentrations are in the range 10-30 mg/l as phosphorus.

Another source:

Phosphate

Phosphates and nitrates are often limiting factors for populations of aquatic plants, algae, and other vegetation. Phosphates are the primary limiting factor in fresh water plant and algal growth. (Phosphorus is necessary for plants in their energy cycles, involving the creation and usage of ADP and ATP.) Nitrates are believed to be the primary limiting factor in control of marine plant growth. However, the synergistic effects of essential trace elements must be considered in both environments. Large amounts of phosphates in a body of water tend to stimulate growth of algae and aquatic plants. If levels become too high, plant growth can accelerate resulting in rivers and lakes with dense growth of algae and plants. This is referred to as an "algal bloom". In 1980, 48% of the lakes and rivers in the United States exceeded the 0.1 mg/liter phosphate standard to prevent the growth of nuisance plant life. Even a level of just 0.025mg/liter will result in an increase in growth of plant life.

Another Source: https://ojs.grinnell.edu/index.php/tillers/article/view/33/33

Many others:

https://tinyurl.com/y3vo3vva

One other point I would like to make. In pool school, Borates are mentioned:

Borate
The borate level can be raised with a combination of borax and muriatic acid, or with boric acid. Borax is described above under raising PH. Muriatic acid is described above under lowering PH. Boric acid is available over the internet from places such as The Chemistry Store and AAA Chemicals. For further information on borates see So you want to add borates to your pool–Why and How.

I don't see how the addition borates are any different in level of understanding and difficulty than the removal of phosphates. Both are unnecessary to maintain a pool properly but both have some benefits that can make maintenance a little easier. So why have we chosen to highlight borates but not phosphates?

Having done both, I find removing phosphates no more difficult than adding borates. In fact, I think removing phosphates was little easier.

 

[JoyfulNoise]

Nitrogen (N), phosphorous (P) and carbon (C, mostly in the form of sugars) are all necessary for life. If any one of those elements are missing, life can not exist. Micronutrients such as potassium (K), calcium (Ca), magnesium (Mg), iron (Fe) and others are all necessary too but in much smaller quantities. None of those elements can substitute for one another, they are all used in different ways and they are all required. When water is deficient in nutrient sources, it is referred to as an “atrophic” condition - meaning it is missing nutrients. When water has too much of any nutrient in it, it is referred to as a “eutrophic” condition. Eutrophication of water leads to uncontrolled and unhealthy algae and bacterial blooms. Pool water is eutrophic but it is also aseptic because of the chlorine sanitizer in it. So while properly chlorinated pool water will not have significant algae or bacterial growth, it is always susceptible to biofouling (unrestricted growth) because of its high nutrient content. Reducing nutrient levels by either chemical removal (precipitation and filtration) or by water replacement will always help to reduce the incident rate and severity of biological growth. Phosphate removal is simply one strategy for making water atrophic.

As for SWGs, that is a more complicated issue. The concept of chloride electrolysis into chlorine is as old as the advent of modern chemistry and is the primary industrial method for producing chlorinating compounds. The processes used in industry are not quite the same as what’s used in a pool but the principle is identical. The problem is, in industry, their input water sources and chloride salts are all pure industrial grade chemicals. Water used in the process has no dissolved chemicals in it. So they never have to consider the effects of what the additions of contaminants can do to their processes. On the other hand, pool water is not only full of salt but also all sorts of contaminants like phosphates, nitrates and dissolved solids. All of these contaminants are susceptible to electrolysis and could, in theory, affect chlorine production. The problem is no one ever studies it because it’s simply not interesting enough to the manufacturer. So unless someone undertakes the time and money to look at the effects of dissolved contaminants on the chlorine production rates of an SWG, there’s nothing left but conjecture and hypothesis. There’s no motivation to study the issue because (A) no one dies from it, and (B) no manufacturer has problems selling thousands of these units per year. Perhaps some brilliant and motivated high school student will stumble upon this topic someday and win a 1st Place ribbon in their school science fair when they figure this out....

 

[AUSpool]

^ very good summary of a long and intensisive examination of nutrients and their impact on pool water chemistry.
Has the electrolysis of nitrate or phosphate ions ever been considered or discussed?

 

[mguzzy]

So unless someone undertakes the time and money to look at the effects of dissolved contaminants on the chlorine production rates of an SWG, there’s nothing left but conjecture and hypothesis. There’s no motivation to study the issue because (A) no one dies from it, and (B) no manufacturer has problems selling thousands of these units per year. Perhaps some brilliant and motivated high school student will stumble upon this topic someday and win a 1st Place ribbon in their school science fair when they figure this out....

Here here.. I suspected it will take a master thesis level work to do the correct analysis... Because I bet no one in the industry would even be interested in putting up a soft money grant to look into it.

^ very good summary of a long and intensisive examination of nutrients and their impact on pool water chemistry.
Has the electrolysis of nitrate or phosphate ions ever been considered or discussed?

I have seen discussions of electrolysis of other ion pairs in the academia lit.... but I don't peruse the industry rags enough to know if there is much presented there.

 

[duraleigh]

Where would the money come from to do an unbiased in depth examination?.......from the folks who sell phosphate removers.

 

[Katodude]

Does TFTestkits sell the 1106? I could not find it on their web site. I was thinking of starting to test and adjust for Phosphates as part of my summer routine this year. Would just like to bundle it in when I order my Tf-100 refills this spring.

Also is the best way to apply the phosphate remover directly to the skimmer?

 

[kimkats]

I will pull @JoyfulNoise into this question as he has good knowledge of this subject. Matt you are up!

 

[ajw22]

Pour the phosphate remover into the deep end of the pool with the pump running.

Phosphate Removers - Further Reading

www.troublefreepool.com

 

[JoyfulNoise]

You can get the 1106 online or directly from Taylor.

I use SeaKlear commercial grade phosphate remover and I add my dose slowly to the skimmer with the pump running. It usually clouds up in about 5-10mins and then clears in about 8 hours. I run continuously for 24 hours after clearing and then an addition 12-24 hours after that. My system pressure usually goes up by 1-2 psi. After that, I tear down the filter and clean it all out with a good high pressure spray clean of all the quad cartridges. Reassemble and add in the DE. I’m usually back at clean pressure after a day.

 

[Leebo]

I ordered the Taylor kit on Amazon but I’d also give Rebecca a call as maybe she’d order one special. Can’t hurt to ask.

I personally slowly pour the phosphate remover in front of the return and follow by a good brushing. I only once had any cloudy water which cleared up overnight.

 

[JoyfulNoise]

It doesn’t matter where you add it. The chemistry is such that it requires time to work (there’s two steps to the reaction) which is why you are typically instructed to wait 48 hours after adding the product BEFORE you backwash or clean out a filter. With sand filters you will need to add either DE or a polymeric clarifier to get fast clearance times. Cartridge and DE filters don’t need any clarifying agents.

 

[Katodude]

I have a cartridge filter so that should make things easier. I just ordered the test kit so I will measure this weekend. I will probably wait a month or so for the water to warm up a little since we have been having a bit of cold spell.

I can also use the robot with the fine filters to pick up an particulate at the bottom of the pool