There is no question that SOME bleaches contain extra chemicals you don't want in your pool such as scents or thickeners, but Clorox Regular bleach is (now) 6% and in fact if you look on the label it also says "5.7% Available Chlorine" because it is specifically designed to be OK for use IN POOLS. Most off-brand Ultra bleach is also 6% though is not labeled as such so is a bit of a risk. Bleach and chlorinating liquid do contain extra salt so for every 1 ppm FC that is added, it also adds 0.8 ppm salt (sodium chloride) and this is in addition to the 0.8 ppm of salt that is added from ALL sources of chlorine when the chlorine gets consumed and is converted to chloride. Technically, 6% bleach is (by weight) 6% Sodium Hypochlorite, 4.7% Sodium Choride (salt), about 0.2% Sodium Hydroxide (lye), and 89% water without any calcium or other substances. An old Material Safety Data Sheet (MSDS) for Clorox Regular is shown
here. I estimated the amount of lye based on the pH of 11.4 in the MSDS, but in any event it's negligible. Furthermore, only Clorox Regular bleach has an explicit usage for use of disinfecting drinking water as listed
here and in the FAQ
here.
In fact, the following is an E-mail "letter" I received from Clorox when asking them some questions as I describe in
this thread. I copy the letter below. Ignore the quantities and FC level they suggest -- they don't know about the FC/CYA relationship and are just following old NSPI recommendations (0.6 - 1 ppm FC is not enough chlorine; NSPI even changed this to 1-3 at some point). Also, we have since found out that Clorox Regular is 6% Sodium Hypochlorite by weight, as specified on the bottle, and that this is 5.7% Available Chlorine (by weight) also as specified on the bottle, and that this is equivalent to 6.17 Trade % (Available Chlorine by Volume) which is what should be used for volume measurements and in pool calculators and when comparing to chlorinating liquid which is generally specified in Trade %.
September 13, 2006
Mr. Richard Falk
(address and reference number withheld for posting on this forum)
Dear Mr. Falk,
Thank you for contacting us about Clorox Bleach - Regular Scent. We always appreciate hearing from our consumers.
For small wading pools that are emptied daily we recommend using 1/8 cup of Clorox Bleach - Regular Scent per 100 gallons of water.
For larger above ground or in ground pools we would recommend the following for initial dosages of the product.
5,000 gallons water - 3 cups bleach, 6,000 gallons - water 4 cups bleach, 8,000 gallons water - 5 cups bleach, 10,000 gallons water - 6 cups bleach, 15,000 gallons water - 10 cups bleach, 20,000 gallons water - 13 cups bleach, 25,000 gallons water - 17 cups bleach, 30,000 gallons water - 20 cups bleach, 35,000 gallons water - 23 cups bleach.
Note: 2 cups = 1 pint, 4 cups = 1 quart, 16 cups = 1 gallon.
One quart of Clorox Bleach - Regular Scent per 6,000 gallons of water will supply approximately 2 ppm (parts per million) available chlorine, but this may dissipate rather rapidly in new water depending on the general sanitation conditions of the pool. Repeat dosage as needed to obtain 0.6 to 1.0 ppm available chlorine. Use chlorine test strips to adjust to the desired concentration.
In chlorinating a swimming pool, mix the required amount of Clorox Bleach - Regular Scent with 10 parts water and feed this solution through a chlorinator into the main water supply line to the pool. The feeding rate should be adjusted so the required quantity of this product will be added uniformly throughout the filling of the pool; or, if the water is circulated through a filter, the bleach should be added throughout one complete circulation. If the product cannot be fed into the main water supply line, mix 1/2 pint of the product with 5 gallons of water and scatter over a portion of the pool surface; repeat until the required amount of the product has been scattered over the entire surface of the pool.
Check chlorine level in pool water at least daily with a pool testing set and add this product as needed to maintain 0.6 to 1.0 ppm available chlorine. One pint of Clorox Bleach - Regular Scent per 6,000 gallons of water will supply approximately 1.0 ppm available chlorine. Frequency of application of this dosage will vary depending on number of people using the pool, weather conditions (sunlight exposure) and general cleanliness of the pool area. Chlorine level for acid-stabilized pools should be maintained at 1.0 to 1.5 ppm available chlorine.
The effectiveness of the chlorine is best when the pool water has a PH range of 7.2 to 7.6. The PH of the pool water should be checked daily using a pool PH testing set and adjustment as necessary.
The regular use of this product, in the above proportions, in the swimming pool usually prevents the growth of algae in the water; however, if algae growth is causing the pool water to look cloudy and uninviting, it may be corrected by doubling the initial dosage of the product for a few treatments. This additional product should be added to the pool in the evening after the pool is out of use so the excess chlorine will be dissipated before the pool is used again.
Avoid skin contact with undiluted product; is such contact occurs, rinse immediately with water. When added as recommended, this product has no deleterious effects on the eyes, nasal passages, or skin of people using the pool and will have no effect on swimming apparel.
Enclosed is also the most current MSDS Document we have on this product. We hope you find this information helpful. You can find all of our MSDS Sheets on-line at
http://www.thecloroxcompany.com/product ... index.html.
I do apologize, this is the only information we have. I apologize, that I am unable to better assist you.
Again, thank you for contacting us.
Sincerely,
Natasha Stevens
Consumer Response Representative
Consumer Services
If you have additional questions or comments, please click here to respond to this email.
