Cal Hypo question

[CarlD]

The Spa shock is twice the price as the spa chlorinator and both are cal hypo with 45% available chlorine! What is up with Arch Chemical?!

What? Are you kidding? Arch is now run by the same guy who ran BioGard. Let's see...Tri-chlor tabs with harmful copper so they can say "dual acting", ...Duration tabs from effective plastic-wrapped to crummy tabs that dissolve in 12 hours...old tabs were 68% chlorine, new are 48%...Cal-Hypo from 68% to 48%...5-Way Drop test kit dropped in favor of 6-way strips....

What's up with Arch? They see the public as sheep to be sheared, flowers to be picked, pigeons to be targeted, suckers to be fleeced.

"You can't cheat an honest man, but never give a sucker an even break and don't wisen up a chump!" -- W. C. Fields in You Can't Cheat An Honest Man

[jnorris]

Here's an update:

Added cal-hypo last night, I premixed in water and added it through the skimmer. I believe I added too much, because now my FC is very high. I diluted 3 parts distilled to 1 part pool water, and it was still pinker than the pink on the color comparator at 3 ppm. So I have at least 12, and most likely higher.

Added muriatic acid today, I believe I added too much, because my PH went from 8.0 to 7.2.

Oh, and BTW, took the sticks out of the chlorinator. I will save them for vacations.

I still have a little mustard algae, but not as much as I did. Pump is running on high 24/7 right now. Is it OK to cut it down to low speed? Should I keep the kids out of the pool? I don't want to fade out the swimsuits. I am going to try to keep the FC level at about 15 for a couple more days, and see what happens with the algae.

Judy

[CarlD]

Judy:
Not to worry, the numbers look good. pH of 7.2 is a little low, but you can swim and you don't need to do anything. With your CYA, when FC drops below 10ppm you can swim. At that time, the splashing kids will aerate your water, and your pH will rise again (No, really! Check the Alkalinity forum). AT WORST you are shocking your pool.
Carl

[Simmons99]

With the algae problem - you should hold your chlorine level at 15ppm until the algae dies. Run the pump 24/7 to filter out the dead algae. Also there is a bleach calculator that you can use to figure out the amount of each chemical required to get to the readings you want.

BTW - when adjusting PH a lot of people here add about 1/2 of what is required - then test 24 hours later and then adjust again. The 7.2 isn't that bad.

[brent.roberts]

Judy

your original post said your TC was 2.0 and FC was 2.0 and that would mean your CC was 0. My first reaction was going to be "why do you want to shock?"
If the water was clear and CC=0 then there is no reason to shock. Then much later I see the you mention mustard algae. That changes things.

Maybe someone with more experience can help both of us here but I would have thought your CC would have been up some if you have mustard algae. OR does mustard algae not yield measurable amounts of CC? So was the test not good or the mustard doesn't cause CC to rise?