Will Superchlorination Clear Phosphates?

Chlorinating, maintaining the right chlorine levels,
chlorine problems. Dichlor, trichlor, cal hypo, bleach,
granules, chlorine pucks and chlorine sticks.
Jack Sparrow
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Will Superchlorination Clear Phosphates?

Postby Jack Sparrow » Sun 05 Aug, 2007 08:40

Quick, simple question-- will superchlorination (>15ppm) clear phosphates?


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Postby chem geek » Sun 05 Aug, 2007 17:55

No. But phosphates are usually not the cause of algae. Usually, Free Chlorine (FC) levels that are too low for the Cyanuric Acid (CYA) level are what allow algae to grow. If you don't have your FC at 11.5% of your CYA level, then I'd shock with chlorine first or possibly do a partial drain/refill to lower your CYA level. Though phosphates are a necessary nutrient for algae, chlorine alone will usually keep algae from growing regardless of how much algea "food" there is.
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Postby Jack Sparrow » Sun 05 Aug, 2007 18:29

Ok, thanks.
Now, considering this 11.5% target FC level. At what threshold is the chlorine to high for swimming, thus requiring you to drain/dilute the water to lower CYA levels.
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Postby chem geek » Sun 05 Aug, 2007 21:31

There isn't any limit, per se, since the amount of disinfecting chlorine is the same, but in practice high levels of CYA of 100 or more requiring 10+ Free Chlorine levels can end up using lots of chlorine (if consumed from sunlight, etc.) and it can be hard to maintain that high a chlorine level. If you can't or don't want to drain/refill part of the water to lower the CYA to the more normal range of 30-50 ppm, then you can use a weekly maintenance dose of PolyQuat 60 algaecide to keep away algae. Most bacteria and viruses require very low amounts of chlorine to kill so it's really algae prevention and you can use an algaecide for that, at least until you get the CYA lower.

Keep in mind that stabilized sources of chlorine such as Trichlor and Dichlor contain CYA and are usually how the CYA gets too high. You either need to use an algaecide or need to switch to an unstabilized source of chlorine such as bleach or chlorinating liquid when the CYA gets high (or you can dilute more such as more frequent backwashing)
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Postby Jack Sparrow » Mon 06 Aug, 2007 07:50

Yes, I'm fully aware of the tablets, etc.-- I'm a bleach guy.
Right now I'm sitting at around 40-45 CYA, so I'm in the safe range.

I think, with the water getting warmer right now, I'll be buying a qt. of PolyQuat 60. I did a quick search and it seems a little tougher to find. Where do you buy yours?

Thanks,
Joe
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Postby chem geek » Mon 06 Aug, 2007 11:34

Sorry I misunderstood. I thought that the question was prompted due to algae and possibly higher CYA levels. You should be able to keep away algae in your 40-45 ppm CYA pool by having a target FC of around 5 ppm with an absolute minimum at all times of 3.4 ppm. The algaecide should be seen more like insurance if the chlorine level drops too low for any reason. I don't use algaecide anymore unless I'm going on an extended vacation (just in case those that stay at the house forget to add chlorine) or upon closing in the winter.

Look for algaecide that has the following name in the ingredients:

Poly{oxyethylene(dimethyliminio)Ethylene (dimethyliminio)ethylene dichloride}

and shows 60% as the amount. The following is a sampling of such products:

GLB Algimycin 600
Robarb Robacide 60
Applied Biochemists Pooltrine 60
BioGuard Algae All 60
Leslie's Algae Control (I think -- check the label, I couldn't find an MSDS)

Do you know the phosphate level in your pool and have you had a hard time keeping away algae even at the recommended chlorine level?

Richard
Dan Y

Postby Dan Y » Wed 08 Aug, 2007 19:35

Richard,

Thanks for all the great information. Do you know where I can buy liquified chlorine for use in shocking so that I don't increase either my hardness or my level of stabilizer? Thanks.

Dan
Guest

Postby Guest » Wed 08 Aug, 2007 21:04

Dan,
You can buy liquid chlorine at WalMart!
Unscented bleach goes around here for $2.28. :D
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Postby chem geek » Wed 08 Aug, 2007 22:21

Dan,

Pool User is correct. Unscented bleach is sodium hypochlorite and is identical to the chlorinating liquid sold in pool stores except it is not as strong. Be aware, however, that only Clorox Regular is guaranteed to be 6% chlorine by weight (5.7% available chlorine; 6.2% trade) and that the normal bottle size is 3/4 gallon (96 ounces) though some larger 1.5 gallons bottles are sometimes available. Usually, the off-brand "Ultra" brand is also 6%, but it doesn't say so on the bottle. Off-brand Regular is often only 3% or less, so be careful.

Chlorinating liquid is sometimes reasonably priced and usually comes at 10% or 12.5% strength and may sometimes be found at hardware stores (Home Depot, OSH) and at Wal-Mart, etc. In my area, I buy chlorinating liquid from my pool store since they are reasonably priced ($3.50 for one gallon of 12.5%), it's less for me to carry, and they reuse the bottles that I return so I feel better about the environment. :D Of course, the choice is up to you.

Richard
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Postby Backglass » Thu 09 Aug, 2007 13:57

I wish I could get a good deal on liquid chlorine from a pool store but mine charges 9.99 a gallon for 12% "Liquid Shock". :shock:

I get the 6% ultra from Wal-mart. $2.49 for 174oz which works out to $1.83 a gallon.
===============================
I'm no expert...just a long time pool owner. The real experts are at www . troublefreepool . com

Download Bleachcalc free at troublefreepool . com /files/BleachCalc262.exe and start saving money on chemicals.
Dan Y

chlorinating liquid

Postby Dan Y » Tue 14 Aug, 2007 19:49

Richard,

The retail pool stores around here say that they can't sell liquid chlorine in my state, Kansas. What? Hard to believe.

If I could find the 12.5% solution, do you know how the cost compares with the use of calcium hypo for shocking? It seems like the liquid would be more expensive. On the other hand, I guess you wouldn't have the residue and the increase in calcium hardness over time.

Shifting gears slightly... Does anyone manufacture the every daily (trichlor) tablets without CYA that I could use in my feeder? It just seems to me that if I take the responsibility of keeping my CYA at the desired level, I should have the choice to use slow-dissolve tablets in the feeder (or other alternative), without the worry of increasing the CYA level.

Dan
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Postby chem geek » Tue 14 Aug, 2007 22:19

This link compares the cost of the various chlorine sources, but keep in mind that such costs vary across the country (especially for bleach and chlorinating liquid). It seems nuts that there are some states that apparently don't allow for chlorinating liquid since it's IDENTICAL to bleach except twice as concentrated and they clearly sell bleach in those states. Sounds like some heavy lobbying from the Trichlor/Dichlor and Cal-Hypo industries if you ask me.

Unfortunately there is no convenient solid slow-dissolving source or chlorine that does not contain CYA or have other problems. Trichlor is slow-dissolving, but has CYA. Dichlor has even more CYA and is very fast dissolving. Cal-Hypo doesn't have any CYA and is usually somewhat slow-dissolving granules (so must pre-dilute in a bucket of water first), but also comes in slow-dissolving pucks (HTH Duration tabs) but these tend to fall apart quickly near the end and leave some gummy residue and they increase Calcium Hardness (CH) though that's not as much in percentage terms as CYA (since CH is typically much higher in concentration in pools than CYA). Lithium hypochlorite does not have CYA nor CH but is VERY expensive and is fast dissolving. And, of course, bleach and chlorinating liquid are bulky and heavy and fast diluting and do not contain CYA nor CH.

If you want more automation, you can either go the saltwater chlorine generator (SWG) route or you can use The Liquidator to automatically dose bleach into your pool.

By the way, if you ever used your feeder for Trichlor, then you cannot use it for Cal-Hypo, and vice versa. The Cal-Hypo HTH Duration tabs require their own special kind of feeder anyway, but mixing Trichlor and Cal-Hypo can be explosive and is a definite no-no. In fact, any acid mixed with Cal-Hypo is bad as it generates lots of heat and can burst into flame.

Richard
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Postby Jack Sparrow » Wed 15 Aug, 2007 07:03

chem geek wrote:By the way, if you ever used your feeder for Trichlor, then you cannot use it for Cal-Hypo, and vice versa. The Cal-Hypo HTH Duration tabs require their own special kind of feeder anyway, but mixing Trichlor and Cal-Hypo can be explosive and is a definite no-no. In fact, any acid mixed with Cal-Hypo is bad as it generates lots of heat and can burst into flame.


I assume Trichlor for sanitizing and Cal-Hypo for shock is ok and safe-- you're concern is about mixing the two pre-introduction to the pool??

Joe
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Postby chem geek » Wed 15 Aug, 2007 11:39

Yes, that is correct. In the pool water, it all becomes the same hypochlorous acid. It's only mixing the concentrated chemicals that is a problem. Adding them separately to the pool water (with some pause to allow them to dilute) is fine. In the inline feeders, there is often some remnants of whatever was used in the feeder and even that small amount of concentrated chemical can be a problem which is why one isn't supposed to reuse such a feeder with a different chemical.
Dan Y

Postby Dan Y » Thu 16 Aug, 2007 20:35

Thanks, Richard. Great information. I thought about the Lithium but you are certainly right about the high $!

Dan

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