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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Posts: 2382
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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.

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