very green water and very high level of chlorine

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
poolgreen

very green water and very high level of chlorine

Postby poolgreen » Fri 21 Aug, 2009 18:11

I have the same problem. I have added colorine and more colorine, bags and bags of shock , anti algi , liquid colorine , new filters, back wash and so on....and yet greener pool. Can any one help?


chaka

very green water and very high level of chlorine

Postby chaka » Tue 25 May, 2010 11:10

haven't tried this yet. but it seems like a good idea.
harry Dorsey

very green water and very high level of chlorine

Postby harry Dorsey » Sat 05 Jun, 2010 14:03

joyschenck wrote:Hello
My problem started last week with my pool . On wed it looked alittle green so i went and purchased algecyde for the pool . the next day my pool was greener then the day before. So i put in more and it made it greener. I then got shock it for the pool and the water was clear but lots of alge on the bottom. I stir up the alge thinking that the filter would take care of it. but it didnt. So i was told to shock it again and use 2 bags. in which i did but water still really green and my chlorine level is really high.
Any advice as to what to do next??
Deanb

very green water and very high level of chlorine

Postby Deanb » Mon 28 May, 2012 00:56

joyschenck wrote:Hello
My problem started last week with my pool . On wed it looked alittle green so i went and purchased algecyde for the pool . the next day my pool was greener then the day before. So i put in more and it made it greener. I then got shock it for the pool and the water was clear but lots of alge on the bottom. I stir up the alge thinking that the filter would take care of it. but it didnt. So i was told to shock it again and use 2 bags. in which i did but water still really green and my chlorine level is really high.
Any advice as to what to do next??





Hi Maybe you have phosphates in your pool, algae grows very fast with phosphates and doesn't let let your chlorine work very well very quickly turning them into chloromides - Dead chlorine so probably just need a phosphate remover, and if luminous green then it could be a a high copper count in your pool which you need a copper remover such as a clarifier hope this helps
chem geek
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very green water and very high level of chlorine

Postby chem geek » Mon 28 May, 2012 01:34

Deanb wrote:Hi Maybe you have phosphates in your pool, algae grows very fast with phosphates and doesn't let let your chlorine work very well very quickly turning them into chloromides - Dead chlorine so probably just need a phosphate remover, and if luminous green then it could be a a high copper count in your pool which you need a copper remover such as a clarifier hope this helps

This is just a bunch of baloney. Chlorine and phosphates do not react with each other and do not turn into chloromides by which I presume you really meant chloramines. Phosphates and nitrates are essential nutrients for algae growth, but chlorine alone can kill algae faster than it can grow even when there are plenty of phosphates and nitrates in the water. Algae growth is ultimately limited by sunlight and temperature taking 3-8 hours to double in population under ideal conditions. If the Free Chlorine (FC) level is consistently maintained at least as high as 7.5% of the Cyanuric Acid (CYA) level, then it will kill green and black algae faster than it can grow (yellow/mustard algae needs to be removed completely -- inhibition rates are higher at 15% of the CYA level so can be impractical). Higher chlorine levels are needed to shock the pool if algae is already present because the proper FC/CYA ratio wasn't maintained. It is CYA that inhibits chlorine, not phosphates. Read the Pool School for more info.
Deanb

very green water and very high level of chlorine

Postby Deanb » Mon 28 May, 2012 02:10

This is just a bunch of baloney. Chlorine and phosphates do not react with each other and do not turn into chloromides by which I presume you really meant chloramines. Phosphates and nitrates are essential nutrients for algae growth, but chlorine alone can kill algae faster than it can grow even when there are plenty of phosphates and nitrates in the water. Algae growth is ultimately limited by sunlight and temperature taking 3-8 hours to double in population under ideal conditions. If the Free Chlorine (FC) level is consistently maintained at least as high as 7.5% of the Cyanuric Acid (CYA) level, then it will kill green and black algae faster than it can grow (yellow/mustard algae needs to be removed completely -- inhibition rates are higher at 15% of the CYA level so can be impractical). Higher chlorine levels are needed to shock the pool if algae is already present because the proper FC/CYA ratio wasn't maintained. It is CYA that inhibits chlorine, not phosphates. Read the Pool School for more info.



Yeah ok so i take it this article about how phosphates work is wrong on this link..... and my commercial pool operators course manual was wrong too which i completed 2 weeks ago oh no so everyone in the world who have just done their course is wrong.

2 extracts from site passage:

1.One traditional treatment to visible algae in pools has been to "shock” the pool with high concentrations of chlorine which kills off most of the algae. However, this does not reduce the amount of phosphate in the pool, so when the chlorine level in the pool drops back to normal, the conditions which allowed algae to grow before “shocking” are still there. And the algae will start to re grow.

2.The biggest concerns for swimming pool owners from increased phosphate levels are excessive, stubborn algae blooms and rapid chlorine consumption.

so as these state phosphates do consume chlorine and after shocking and then because there is still phosphates in the water the algae grows back.
Deanb

very green water and very high level of chlorine

Postby Deanb » Mon 28 May, 2012 02:11

Deanb

very green water and very high level of chlorine

Postby Deanb » Mon 28 May, 2012 02:22

But chem geek you are right but algae grows back quick as phosphates need to be removed to eliminate the problem all together. shock clean then phos remover then test if still present then more phos remover untill none.
chem geek
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very green water and very high level of chlorine

Postby chem geek » Mon 28 May, 2012 12:18

As that link stated, "Preventing algae from regrouping requires that either the chlorine concentration is kept at high levels or that the conditions in the water are changed to be less favorable for algae growth." This is true, except that "high levels" for chlorine does NOT mean a particularly high active chlorine level. It takes only a hypochlorous acid level of around 0.03 ppm to kill green and black algae faster than they can reproduce regardless of nutrient level. Yes, you read that right. So why is it that pools get algae even though they have chlorine in them? The answer is Cyanuric Acid (CYA) aka stabilizer or conditioner.

CYA significantly lowers the active chlorine (hypochlorous acid) level in pools. When the Free Chlorine (FC) level is around 7.5% of the CYA level, over 97% of the FC is bound to CYA and does not kill algae, disinfect, nor oxidize to any great extent. This is known science since at least 1974 (with this paper). At this FC/CYA ratio, there is only 0.03 ppm hypochlorous acid and 0.03 ppm hypochlorite ion (at pH 7.5). The reason that many residential pools get algae is that most use Trichlor pucks/tabs where the CYA level increases over time while people do not increase their FC target over time (i.e. the FC/CYA ratio drops over time). The following are chemical facts that aren't taught even in your Certified Pool Operator's (CPO) training course:

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

At 2 ppm FC per day, Trichlor increases CYA by over 35 ppm per month if there is no water dilution. I strongly suggest you read Certified Pool Operator (CPO) training -- What is not taught if you want to know more.

My own pool has had over 3000 ppb phosphates and there are other pools with over 5000 ppb phosphates (and lots of nitrates as well) that have no algae growth because the proper FC/CYA ratio is maintained. There is no question that such pools are more "reactive" if you let the FC/CYA ratio get too low since the algae do grow more quickly with the higher levels of nutrients, but there is a limit to such growth based on sunlight and temperature where algae double in population in 3-8 hours under ideal conditions. If you've killed off the algae and maintain the proper FC/CYA ratio, then chlorine kills any new algae getting into the pool faster than it can reproduce.

The current recommendations by many saltwater chlorine generator (SWCG) manufacturers of 1-3 ppm FC with 60-80 ppm CYA is NOT sufficient to prevent algae growth which is why you see problems in some of these pools. It doesn't even show up as algae initially, but rather as a mysterious chlorine demand where one can't seem to maintain or get a chlorine level. There is no mystery here -- nascent algae growth consumes the chlorine as fast as it is reproduced IF you let things go too far so that there is enough algae present to create that amount of consumption. For SWCG pools, the minimum FC is 5% of the CYA level so 4 ppm FC with 80 ppm CYA would work, but only if you got ahead of the algae in the first place (i.e. shocked the pool to kill off the algae, if it is already present).

There are tens of thousands of pool owners at The PoolForum and Trouble Free Pool who maintain their pools according to either the Best Guess Swimming Pool Chlorine Chart or the Chlorine / CYA Chart. Most of these pool owners (including myself) use only chlorinating liquid or bleach (or have SWCG systems) and do not use any algaecides, phosphate removers, clarifiers, flocculants, enzymes or even shock regularly. We maintain our pools based on known science, not on what the industry says in order to promote highly profitable products.

Now if you are a service tech and only visit a pool once a week, then that's a different story. Though there are some in sunny desert areas that use high 100 ppm CYA levels and use chlorinating liquid (or chlorine gas) to raise the chlorine to 14 ppm which then drops to around 4 ppm the following week when more chlorine is added, most use Trichlor tabs/pucks for continual dosing. Since the CYA builds up making chlorine less effective, they need to do something to prevent algae growth so add algaecides such as Polyquat, or they add borates (Proteam Supreme, Optimizer, etc.), copper ions, or use phosphate removers. These are all extra cost, of course. My local pool store runs a pool service for around 2000 pools and they try and maintain 4.5 ppm FC and dilute the water if the CYA gets above 100 ppm. Even so, a small number of pools get algae and need shocking or algaecide or phosphate remover. Again, not a surprise since their target FC is a little too low for the maximum CYA level they allow.

In some areas, the CYA buildup is not a problem because the pool seasons are short, the pools are smaller, sand filters are used so have regular backwashing, and there is summer rain overflow so CYA doesn't get high enough to be an issue and winter rain overflow dilutes the CYA even further for the next season. However, other areas have no summer rains, use over-sized cartridge filters with infrequent cleaning, have larger pools, and longer swim seasons so the CYA builds up more quickly.

I'm not saying that phosphate removers don't work, but rather that they should be seen in the same vein as algaecides. They are something that is not necessary if you maintain the proper FC/CYA ratio, but can be used as insurance if you are unable or unwilling to do so.
Deanb

very green water and very high level of chlorine

Postby Deanb » Mon 28 May, 2012 23:43

oh of course if the correct level is maintained yes it will stop the whole problem in the first place but what you have to realize is that keeping a low reading of 3ppm chlorine (commercial pool) is not enough to overpower the speed in which algae grows when a high level of phosphates is in the water, and if you go over the level of 5 ppm the pool has to be shut down now if you dont get rid of the phosphates then when you lower the levels back to 3 ppm the algae will grow again therefore not stopping the problem, i am in a very harsh area we have alot of iron ore dust and a lot of tough surviving foliage which have high levels of phosphates which over time cause higher levels of phosphates in the water creating this problem, you are right about the CNA levels but the best way to fix a pool is by doing it as if it was a commercial pool and it is a requirement by many com pools to have no CNA as this reduces the likely hood of going over the 5ppm. also if you have a green pool and throw in stablised chlorine it can go very milky, for this reason we use ezi chlor.... a very low stablised level chlorine that does not cloud up the water and kills quick, then we use a phosphate remover then a chlorine neutralizer to bring down to 3ppm and then resume normal operation, the handbook does tell you about phosphates on page 83 pool and spa water problems.
chem geek
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very green water and very high level of chlorine

Postby chem geek » Tue 29 May, 2012 01:42

We're talking residential pools, not commercial pools, and residential pools are not shut down because the FC is too high. Even commercial/public pools are not necessarily shut down when the FC is over 4 ppm. The limit in Florida, for example, is 10 ppm as shown here and Texas allows 8 ppm as shown here. The EPA limit of 4 ppm for drinking water is in the FIFRA rules for product labeling, but it is state and county regulations that determine the actual limit used in commercial/public pools.

I have the 2009 "CPO® Handbook, National Swimming Pool Foundation®" with front cover title "Pool & Spa Operator™ Handbook" right in front of me where on page 83 it talks about phosphates and nitrates being nutrients for algae, but nowhere does it even refer to phosphate removers (that's something I suggested they do in the future). Instead, they end with the following:

Since all the nutrients that algae needs, including phosphate and nitrate, are commonly available in pool water or are stored within algae, it is very important that disinfectant residuals be maintained at all times to prevent the growth of algae.


So when you are going to be referring to sources to bolster your argument, you should actually make sure they are truly consistent with the points you are making. In this case, they are not though I believe that is flawed and that the manual should refer to phosphate removers as another alternative to using algaecides when one is unwilling or unable to maintain a sufficient active chlorine (hypochlorous acid) level (i.e. FC/CYA ratio). In fact, the first paragraph in the Algicides section of the manual on page 82 states the following:

Disinfectants that chlorinate or brominate the water kill and prevent the growth of algae. Algae (and bacteria) prevention has driven more commercial facilities to install automatic chemical feeders, controllers, and probes to maintain adequate disinfectant levels at all times. Facilities without these mechanical systems are at a greater risk to have algae grow, since pool water almost always contains the nutrients algae need and there are likely times when the disinfectant is absent.


3 ppm FC would be OK if the CYA didn't get much above 30 or 40 ppm, but in pools that use stabilized chlorine, the CYA keeps increasing. High bather load commercial/public pools have most of the chloirne loss from bather load rather than from sunlight so have little need for a CYA level higher than around 30 ppm so there really is no excuse except that many such pools are unfortunately not using unstabilized chlorine (e.g. chlorinating liquid or a saltwater chlorine generator). Again, we've got tens of thousands of residential pool owners who manage their pools without phosphate removers, algaecides or other products -- just chlorine alone to control algae growth regardless of phosphate and nitrate levels. Because most chlorine loss in such low bather-load outdoor pools is from sunlight, the CYA level tends to be higher, around 50 ppm or so up to 80 ppm in sunny areas and in pools using SWCGs, BUT the FC level is raised proportionally relative to the CYA level -- that is the key to keep the same active chlorine (hypochlorous acid) level.

If you find it easier to use phosphate removers or algaecides at extra cost, then that's perfectly fine to do. Just don't fool yourself into thinking it is the only way to prevent algae growth.

By the way, when you refer to Ezi-Chlor, are you referring to the Clearwater Ezi Chlor peristaltic pump for automatically dosing chlorinating liquid or bleach or are you referring to Ezi-Chlor which is granulated Trichlor? If the latter, then for every 10 ppm FC you add, it also increases CYA by 6 ppm. That would not be keeping your CYA low unless you had significant water dilution. According to this MSDS, the product is a combination of Trichlor and borates where the latter helps balance the pH, but also accumulation of higher borate levels (around 50 ppm) is an algicide that you could instead separately add either from a combination of 20 Mule Team Borax and acid or from boric acid.

Also, you refer to having water with algae turn cloudy when you shock with chlorine as a bad thing, but that's what ANY chlorine source will do since it bleaches out the chlorophyll in the algae and then the algae needs to be further broken down or filtered out. Stabilized chlorine isn't the cause of that specifically. Cal-Hypo can cloud the pool if it is already saturated with calcium carbonate (e.g. a plaster pool).
Guest

very green water and very high level of chlorine

Postby Guest » Mon 23 Jul, 2012 12:43

I had the same problem last summer. We finally hired a pool man. I was spending so much money in chemicals. When the pool man came he said that the algicide I had poored in makes the pool use so much more chloiene. Hum the pool store forgot to mention this to me. The more algicide the more cloriene you will rip threw. The pool man used liquid cloriene and we ran the pump for several days t get it backk. Also, you need to drain and re fill the pool every few years. You have to start with fresh water sometimes.
chem geek
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very green water and very high level of chlorine

Postby chem geek » Tue 24 Jul, 2012 20:57

If you manage your Cyanuric Acid level by not always using stabilized chlorine (Trichlor, Dichlor), then you wouldn't need to refill your pool water. The chlorinating liquid (same as bleach, but stronger in concentration) is key. You do want to have some water replacement over time so that the salt level is kept somewhat in check, but usually winter rains are sufficient for that (depending on where you live).
reacer2

very green water and very high level of chlorine

Postby reacer2 » Sun 01 Sep, 2013 16:49

joyschenck wrote:Hello
My problem started last week with my pool . On wed it looked alittle green so i went and purchased algecyde for the pool . the next day my pool was greener then the day before. So i put in more and it made it greener. I then got shock it for the pool and the water was clear but lots of alge on the bottom. I stir up the alge thinking that the filter would take care of it. but it didnt. So i was told to shock it again and use 2 bags. in which i did but water still really green and my chlorine level is really high.
Any advice as to what to do next??
racer2

very green water and very high level of chlorine

Postby racer2 » Sun 01 Sep, 2013 16:57

my pool 15,000 gallons it turned green on me i put in 5 gallons of clorinrine and yellow out which usually works but now its getting greeneri have a sand filter? whats going on.

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