Bleach

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
chem geek
Pool Industry Leader
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Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

Postby chem geek » Sun 09 Mar, 2008 20:27

The 1 gallon of bleach per 1,000 gallons, if the bleach were Clorox Regular or an off-brand Ultra at 6% concentration, would raise the FC to nearly 62 ppm so would be WAY too high. You are correct that it probably should have been 1 gallon of bleach per 10,000 gallons which would raise the FC by 6.2 ppm which is far more reasonable (assuming there is some CYA in the water).

Also, it is not true that bleach or chlorinating liquid will raise the pH permanently. It does raise it upon initial addition, but the usage of chlorine from breakdown from sunlight and oxidation of ammonia/urea and organics is an acidic process that exactly compensates for the pH rise (except for a SMALL rise from excess lye). Technical details of this may be found here .

If the pH rises when using bleach or chlorinating liquid on an ongoing basis, then it is due to outgassing of carbon dioxide (pools are intentionally over-carbonated to provide a pH buffer and prevent dissolving of plaster) and the solution is to lower the TA level which reduces the tendency of the pH to rise. I only use 12.5% chlorinating liquid in my own pool (no other chemicals) and my pH is rock solid over time. I also have an opaque electric safety cover so the outgassing of carbon dioxide is minimized (and I keep my TA at 80). Even with use 5 days a week, I only need to add chlorine twice a week as it only uses around 1 ppm FC per day (since the opaque cover keeps out the UV rays of the sun when the cover is closed).

Richard


slprncess

Bleach

Postby slprncess » Sat 24 May, 2008 20:13

I have posted another post about algae in my pool and I am trying to get rid of. I have purchased new system 3 filters and am wondering how i should tackle this. Should I drain or try to clear up with the new filters and chlorine or bleach? I have read that bleach is much less expensive then liquid chlorine. How much bleach should I use to clear up my pool? It is between 15-25,000 gallons. Sorry havent exactly measured. I really dont know how to measure. This is just a assumption.

Please help!!
chem geek
Pool Industry Leader
Pool Industry Leader
Posts: 2382
Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

Bleach

Postby chem geek » Sun 25 May, 2008 05:42

Use The Pool Calculator to figure out how much chlorine to add. Chlorinating liquid is not always that much more expensive than bleach. First of all, you should only be looking at bleach that says its concentration such as 6% for Clorox Regular or off-brand Ultra (off-brand Regular is sometimes 3% or less). Second, realize that 12.5% chlorinating liquid at $3.65 per gallon (the price I pay for what I use) is equivalent to $1.35 per 96-ounce (3/4 gallon) jug of bleach.
slprncess

Bleach

Postby slprncess » Sun 25 May, 2008 15:07

chem geek wrote:Use The Pool Calculator to figure out how much chlorine to add. Chlorinating liquid is not always that much more expensive than bleach. First of all, you should only be looking at bleach that says its concentration such as 6% for Clorox Regular or off-brand Ultra (off-brand Regular is sometimes 3% or less). Second, realize that 12.5% chlorinating liquid at $3.65 per gallon (the price I pay for what I use) is equivalent to $1.35 per 96-ounce (3/4 gallon) jug of bleach.


Would you suggest just trying to clear up with chlorine or should i drain if it is that bad? i dont want to spend all this money on chlorine for it to do nothing!
sqompy

pool turning green already

Postby sqompy » Wed 16 Jul, 2008 08:37

I have just replaced my liner and started filling my pool (27Ft round). It is not even half full and already has a tint of green. This happens every year no matter what I do the darn thing turns green. The pool place just keeps telling me to use the shock (granules) and it does nothing. Should I try to put bleach in the pool now before it gets any worse? How much bleach should I put in 18,400 gal water?
Guest

Bleach

Postby Guest » Wed 16 Jul, 2008 15:08

In order to give advice on any pool you have to know the chemical balance of the water.

I would get your fill water tested to see what chemical levels you have. From there you can get advice on what to add.

In general, you will need chlorine. Most forms of chlorine will add other products to the water. If you need those extra products then it could be a good form of chlorine to use. Until you have a full set of chemical balance numbers you can't tell what would be best.
thinkpool

Green Algae (Mustard)

Postby thinkpool » Mon 18 Aug, 2008 08:00

:(
I have serious green algae problem. All the values tested are within range. I used pool calculator to figure out the amount Bleach needed. But, the result was ineffective. FC= 2-5 Ph~ 7.5, so I added 2.7 gals of Chlorox in the night and same color "mustard green" next morning. Test again, FC= 7-8 Ph~7.8. Do I continue with Chlorox treatment? :?:
Thanks in advance for any advise!!!
chem geek
Pool Industry Leader
Pool Industry Leader
Posts: 2382
Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

Bleach

Postby chem geek » Mon 18 Aug, 2008 11:18

"all the values are in range" is not a complete set of test results. What is the Cyanuric Acid (CYA) level? Also, has the water been tested for copper or is the water a "clear green" as opposed to cloudy or looking like algae. You should really get your own test kit. You can get the Taylor K-2006 kit at a good online price here or you can get the TF100 kit from tftestkits(dot)com here with the latter kit having 36% more volume of reagents so is comparably priced "per test".
thinkpool

Bleach

Postby thinkpool » Mon 18 Aug, 2008 11:33

Thanks. CYA= 150 and cloudy mustard green. I think "mustard green" means copper present. :D :?
chem geek
Pool Industry Leader
Pool Industry Leader
Posts: 2382
Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

Bleach

Postby chem geek » Mon 18 Aug, 2008 13:34

150 ppm CYA is way too high. To prevent algae growth in a manually dosed pool, you would need to keep a minimum Free Chlorine (FC) level of at least 11 ppm and I doubt you were doing that. You need to do a partial drain/refill to get your CYA lowered. You should also consider switching from using Trichlor to using chlorinating liquid or unscented bleach for at least part of your chlorine needs. For every 10 ppm FC added by Trichlor, it also increases CYA by 6 ppm so unless you have a lot of splash-out, a small pool, and a filter that is backwashed weekly, you can end up having the CYA rise in just one or two seasons.

You can learn more about pool water chemistry and properly managing a pool at Pool School.

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