Swimming Pool Chemistry - Lowering TA/pH

Why is the "slugging" method of getting muriatic acid into a pool used to lower TA and why is "broadcasting" used to lower pH. In other words, what happens chemically when a product is slugged into a pool as opposed to sprinkling it all around. One would think that the end state is the same.
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Unless one thought that reaction kinetics varied with pH in the reactants, and pH being a measure of dilution/concentration. Adding 10 units of 0.1M acid is not the same as adding 1 unit of 1.0M. Dilution, or promoting faster dilution by broadcasting, matters.
Whether it matters in the superstitious minds of pool technicians versus the reality of a pool, with these particular reactants, is another question.
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That makes sense, thank you for the answer.
On another matter I would be curious to hear your opinion on the suggested practice by the industry of superchlorinating a pool every week. Actually the interval varies depending on who you talk to. I am under the impression that if you maintain your ORP at 650 then this is not needed, upsetting the pool industry because you're not buying these little bags of 75% cal hypo at 3 times the price of the 70% stuff in your big bucket.
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Paul Giroux writes:

Superchlorination is the best way to clean up accumulated problems. Residential pools tend to accumulate problems, because they tend to fall below minimum sanitation at a moment's neglect. Moreover, with the CYA scheme, there's hardly enough chlorine to keep you from getting sick, and not enough to keep the pool clean, thus the need for routine superchlorination.
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The first season of owning a pool, I used tons of chlorine. Then I found out about stabilization. This is cyanuric acid. If you don't have it in the right balance, the chlorine you have leaves through the surface quickly.
Pool stabilizer is about $20. A test kit is about $20. Those buckets of 3" tablets are about $60 on sale. I have not had to add stabilizer for three years, except when I drained it for replastering.
When buying those chlorine tablets, look for stabilized chlorine. It stays in the water longer.
"Shocking", or superchlorination is needed occasioinally, but that chlorine is unstabilized, so it doesn't keep the high chlorine levels for as long. I buy the 5 gallon bucket of NASTY granules, and use that about two cups at a time once a month, or when I need to for heavy use, or the start of algae. The big buckets are WAAAAY cheaper than those $2 bags.
Just my experiences. Your results may vary.
Steve
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SteveB writes:

Not really:
http://www.truetex.com/poolcontrol.htm
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On Tue, 10 May 2005 16:44:54 -0500, Richard J Kinch

Look here http://www.tubgirl.com
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It's been a while since I visited that page, thanks!
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And the stabilizer stays in there forever and accumulates until you reach 'chlorine lock'. I much prefer using cal hypo, that way I can 'manage' the cya myself. I know what's in there right now, nearly 10 ppm and no more. Later this summer I know I'll have about the same amount. Every evening I do a quick check of the pool and add chlorine, usually 1/4 cup of 70% cal hypo, about $0.20 a serving.
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