Extremely High Phosphate count

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Extremely High Phosphate count

Postby Laura » Sun 02 Nov, 2008 14:06

We have had a problem with phosphates in our pool since June. There was yellow and green alge in the pool at that time. We treated it as per our local pool place's specifications and the alge did clear up, but since then we have had off the chart readings on phosphates. We have tried numerous processes suggested by the pool place, including having them send out one of there service people to check out the pool. We do have a Clormatic salt generating system. It obiviously has not been able to work since the phosphate count is so high. What do you suggest we do to try and get the phosphates under control. (We have cleaned our DE filter three times: July 4th , August and Oct.)
Laura
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Extremely High Phosphate count

Postby chem geek » Sun 02 Nov, 2008 14:36

How high is "off the chart" in phosphates? My pool has at least 2000-3000 ppb phosphates (my fill water has 300-500 ppb phosphates and fertilized soil sometimes gets blown into the pool) and I prevent algae by making sure the Free Chlorine (FC) level doesn't drop below 7.5% of the Cyanuric Acid (CYA) level (it's a manually dosed pool). For an SWG pool, the FC should never be allowed to drop below 5% of the CYA level.

Do you know the CYA (aka stabilizer or conditioner) level in your pool? What FC do you normally maintain in the pool? The pool industry recommendations of maintaining 1-3 ppm FC with 60-80 ppm CYA in an SWG pool are NOT sufficient to prevent algae growth without the use of a supplemental (i.e. extra cost) algaecide such as PolyQuat 60 used weekly or using a phosphate remover to lower phosphate levels. It is NOT necessary to lower the phosphate level, but it IS one of several options. Just maintaining the proper FC level relative to CYA is the cheapest approach (i.e. minimum of 4 ppm FC with 80 ppm CYA, for example), but if you want to have a lower chlorine level you can use a weekly algaecide (PolyQuat 60) or use a phosphate remover. However, a phosphate remover will be expensive in lowering a high phosphate level and it will precipitate a lot that will need to get removed via vacuum to waste or multiple filtering/backwashing cycles.

You can learn much more about maintaining your pool as well as how to shock it to get rid of algae here.

Richard
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Extremely High Phosphate count

Postby shjunliantech » Wed 05 Jan, 2011 21:52

Lanthanum products are a potent and specific phosphate remover. They are best suited to maintaining low levels of phosphate in pools where performance and convenience are important. They are easier to use and apply than aluminium products and do not require vacuuming to waste after their application. One of the main advantages of lanthanum is that its ability to form lanthanum phosphate is not affected by the pools water balance.

A small amount of lanthanum compound will cause the phosphate level to drop below 100ppm, while concentrations of below 10ppb are easy to maintain.

Lanthanum compounds work by lodging in the pools filter media or cartridge, slowly dissolving to lightly coat the filter media. As phosphate rich water passes over the lanthanum crystals, they chemically attach themselves to the phosphate - forming lanthanum phosphate. Lanthanum phosphate is not suitable as a nutrient, and binds into larger particles so it can be removed by the pools filter medium. Large quantities of lanthanum can be stored in the filter without clouding the pools water.

While phosphate will accumulate in a pool naturally, there are steps pool owners can take to prevent excessively high levels.
- Do not allow runoff from gardens and lawns to enter the pool
- Remove leaves from the pool regularly and promptly
- Apply a lanthanum compound phosphate remover regularly
- Have the pools water tested by a professional.
Our new phosphate removal method provides the most efficient way available to remove or lower phosphate levels. A chloride based formula; one quart of our Phosphate Remover is capable of taking 1,000 ppb (parts per billion) of orthophosphate out of 20,000 gallons of pool water. In addition, there are other benefits:
• Cost Effective – Removing orthophosphate is less expensive than fighting a persistent algae growth.
• Short Duration Turbidity – High concentrations of orthophosphate can cause some cloudiness that usually lasts less than 24 hours.
• No Excess Carbonate Build-up – Because it is a chloride compound, no carbonate is added to contribute to scale formation.
• No Vacuuming – Filtration system will remove the precipitate to be backwashed to waste.

EASY TO USE
• Test for Phosphate using a phosphate test kit.
• Use chart on product to determine correct dosage.
• Pour proper amount of Phosphate Remover into skimmer with system running.
• Run filtration system for 24 hours watching filter pressure. Clean or backwash as needed.
• Test for phosphate monthly and use Phosphate Remover to keep phosphate levels below 125 ppb.
• For faster and more efficient results, add 4 in 1 Clarifier following Phosphate Remover .
• Phosphate Remover and 4 in 1 Clarifier are available in one-quart bottles.

If you are interested in our lathanum chloride solution, please feel free to contact emma emma.wei2 at junliantech.com
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Extremely High Phosphate count

Postby Laura » Sun 24 Jul, 2011 17:11

Okay, I have read the response and I have the same problem as the person before me.

However, your remark was to try to alleviate run off from gardens....well we have very large fields all around us and we have well water.

We were told the filter does not filter out phosphate and we have to use a product that makes it sink to the bottom, vacume and backwash. Problem is every time we have to add water, we are in the same position.

So how do we keep up?

Thanks
Laura
 

Extremely High Phosphate count

Postby chem geek » Mon 25 Jul, 2011 01:53

If you maintain a Free Chlorine (FC) level high enough relative to the Cyanuric Acid (CYA) level, then you will kill algae faster than it can grow regardless of phosphate or nitrate levels. Algae is ultimately limited in its growth rate based on sunlight and temperature (rough 3 to 8 hours for each doubling in population in ideal conditions). See The Pool School including the chlorine / CYA chart.
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Extremely High Phosphate count

Postby Sds » Thu 28 Jul, 2011 16:47

My experience with my swg is that if the phosphates are too high, the cell does not function properly (reads the mineral level too low and does not generate chlorine). Get rid of the phosphates and I suspect you will solve the problem. The advice on fc and cya levels that was given sounds right for a traditional pool, but not for a salt pool.
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Extremely High Phosphate count

Postby chem geek » Fri 29 Jul, 2011 01:40

Sds wrote:The advice on fc and cya levels that was given sounds right for a traditional pool, but not for a salt pool.

That isn't true. There are literally thousands of SWG pool owners who are able to operate their pools regardless of phosphate level (some are above 3000 ppb), but the normally recommended 1-3 ppm FC with 60-80 ppm CYA is NOT sufficient. The FC has to be a minimum of 5% of the CYA level so 3 ppm FC with 60 ppm CYA or 4 ppm FC with 80 ppm CYA and that is AFTER any existing nascent algae growth is killed off by shocking the pool at an FC that is 40% of the CYA level.

Nevertheless, if one wants to spend more money on phosphate removers or on supplemental algaecides, they are welcome to do so. It is true that these products should be seen as insurance IF one ever lets the FC level get too low relative to the CYA level since both phosphate removers and algaecides (Polyquat, borates, copper ions) all slow down algae growth making the pool less "reactive". However, algae growth is ultimately limited by sunlight and temperature REGARDLESS OF PHOSPHATE AND NITRATE LEVELS and that growth rate is roughly doubling in population every 3 to 8 hours. Chlorine can kill the algae faster than it can grow, but if you've already got nascent (even non-visible) algae growing, then the pool can be consuming chlorine faster than the SWG can produce it. This is why one needs to shock the pool in this situation to kill off the algae and then maintain the appropriate FC/CYA ratio.
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Extremely High Phosphate count

Postby silly » Mon 01 Aug, 2011 20:17

Laura wrote:We have had a problem with phosphates in our pool since June. There was yellow and green alge in the pool at that time. We treated it as per our local pool place's specifications and the alge did clear up, but since then we have had off the chart readings on phosphates. We have tried numerous processes suggested by the pool place, including having them send out one of there service people to check out the pool. We do have a Clormatic salt generating system. It obiviously has not been able to work since the phosphate count is so high. What do you suggest we do to try and get the phosphates under control. (We have cleaned our DE filter three times: July 4th , August and Oct.)
Laura


A dedicated phosphate remover is required to get the pool under control. Regardless of what the users are saying, if your phosphates are not under 100ppm, you will have issues affected by then. If the users avoid the issues regardless of their phosphate issues > 100ppm, they are sinking more money into their pool than necessary. A phosphate remover only costs 17.99 per qt here, which is far cheaper than the chemicals you invest in the long run should you neglect it. If you do not use the phosphate remover and apply what chemicals are necessary to balance the pool, I highly doubt you will see appropriate corresponding readings. Phosphates will primarily mess with your chlorine levels because they act as food for algae (causing you to burn through chlorine extremely quickly) however you may see other imbalances resulting from phosphates as well.

As far as phosphates are concerned, when you opened the pool, did you have alot of debris in it? Do you use a phosphate free detergent? Have you or your neighbors fertilized recently? These are all potential causes of phosphates entering your pool.
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Extremely High Phosphate count

Postby chem geek » Tue 02 Aug, 2011 12:44

Phosphates are food for algae (as are nitrates), but if one kills off the algae and prevents it from reproducing by appropriate chlorine levels, then the phosphate levels do not matter. Think of phosphates like wood fuel for a fire where the fire is algae. Think of chlorine at sufficient levels relative to CYA as water to put out the fire. It doesn't matter how much wood there is nor how many matches you use to try to start a fire, if there is sufficient water putting out the fire a conflagration will not get started and the amount of water needed to prevent a fire is very small (compared to what it takes to put out an already started fire).

But then again, phosphate removers are very profitable products for pool stores and manufacturers and there is no question they take the edge off of algae growth IF one does not maintain the appropriate FC level relative to the CYA level. There are thousands of SWG owners, many of whom had very high phosphate levels (I don't have an SWG, but have had 3000+ ppb phosphates in the past) and maintain their pools with an FC that is a minimum of 5% of the CYA level. It can be done, but it is true that IF one lets the FC/CYA ratio drop too low, then algae can start to grow creating at first an invisible chlorine demand, though this can be killed off by shocking.

Bottom line, phosphate removers should be seen in the same vein as algaecides (such as PolyQuat 60). They are insurance. Not necessary, but an option if one does not believe they can maintain an appropriate chlorine level relative to CYA.
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Extremely High Phosphate count

Postby sbrubaker » Wed 22 Feb, 2012 14:15

We have high phosphates but we are an indoor pool. I'm not sure (as well as our professional pool company) were the phosphates are coming from. The source water is low in phosphates but when testing the pool & hot tub, we have extremely high phosphates (roughly 800-10,000). We keep our FC between 2.0-4.0 to sanitize any "critters" We are an indoor pool and therefore do not use any cyanuric acid. The problem that we have experienced with having high phosphate levels, is that it makes the probes testing ORP go crazy. Is there anyway to ward against having high phosphates? (remember we are an indoor pool and don't have to deal with run-off, leaves, fertilizers, etc.)
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