Pool shock

[SueMarkP]

How often do you pool people shock your pools? I hear people mention weekly, but I can keep my free chlorine close to proper levels most of the time just with my chlorine feeder and stabilized chlorine tablets. Occasionally, I'll toss in some additional unstabilized chlorine if I notice the levels have gone down to 1 ppm. As this dissipates over a day the feeder catches things back up. I keep my stabilizer (cyanuric acid) level at around 40 - 50 ppm.

Is shocking something that must be done on a periodic basis to fix something chemically, or is it not required as long as you keep the free chlorine in the proper range? I typically shock about 4 times a season just so I can say I do it. The pool will have an excessively high chlorine level for 2 to 3 days when I do this, which is another reason why I don't like to shock.

[Tom]

.>How often do you pool people shock your pools? I hear people mention weekly,

Sounds good to me, I think they'd have you shock much more than necessary so you'll buy more chemicals. My pool's fine, and I rarely shock it. Keep proper ph, a residual of chlorine, and filter/sweep a lot. Tom Someday, it'll all be over....

[Dave Solly]

"SueMarkP" wrote in news:YSGkc.2026$IG1.65852@attbi_s04:

I do pretty much as you do, and I don't have any problems.

[Travis Jordan]

Here in Florida I have a chlorine feeder but still have to super chlorinate my inground pool about once a month during the summer. The summer rains (and runoff from the deck) contaminate the pool and algae will start to grow - that's when I shock it.

[Nancy]

How long should you typically wait after shocking, before going in? Nancy :-)

[Travis Jordan]

/snip/

If you use chlorine (as opposed to a persulphate) then you need to wait until the free chlorine level has dropped below 10 ppm. Usually 24 hours will do it.

[Richard J Kinch]

Superchlorination is not needed "routinely". It is needed to fix problems that accumulate, such as from letting the chlorine get too low, or a sudden demand from introduction of something foul.

If you use "stabilizer" (marketing term) then you are crippling the chlorine and you will run into problems requiring superchlorination more often.

[JMagerl]

In Chicago area, the rule I use is: Shock at opening and closing and then after each rainfall of 1 inch or more. Rainfall is a big chlorine load.

[Nancy]

Was at the pool shop today, and Bioguard sells SmartShock. It says you can go into the pool after only 15 minutes. Also, you can just add it right to the pool, you don't have to dissolve it like the other shock requires and I think through the skimmer. Just thought I'd post that. Also, the guy told me to shock once a week. Shock and chlorine is all that I should need to keep the pool in tiptop shape all summer. We shall see how we do! Nancy :-)

[Travis Jordan]

Interesting - According to the 'net, Smart Shock has copper and stabilized chlorine as the active ingredients. Perhaps it is a lower concentration of chlorine that lets you swim after 15 minutes. Most of the "quick swim" products use Potassium monopersulphate (i.e. Blue Wave's Chlorine Free Shock).

I hope there isn't too much copper in the Smart Shock product since I can see stains being a problem over time, especially on gunite pools. You might want to consider a sequestering agent if you use a lot of Smart Shock.

202828 - (5185 - 493) BIO-LAB INC. BIOGUARD SMART SHOCK USE: DISINFECTANT - FOR THE CONTROL OF BACTERIA AND ALGAE IN SWIMMING POOLS TYPE: SECTION 3 REGISTRATION - ACTIVE INGREDIENT(S): COPPER SODIUM DICHLORO-S-TRIAZINETRIONE CAS NUMBER(S): 7440-50-8 , 2893-78-9

[Richard J Kinch]

Your guy is mistaken.

[Bill]

The pool supply people tell me I should shock about once a week or after heavy pool usage, which ever comes first. If you have a bunch of people in your pool you need to sanitize because in variably someone is going to pee in your pool. I understand that if someone who has had diarrhea gets into your pool the water will be so unsafe you may need to replace all the water. I just super chlorinate it!

Bill

[JMagerl]

Shocking a pool is not without it's down side. Doing it too often can not only cost you money on the unneeded shock but also on repair bills later on. Bleached liners and degraded plastic parts (in filters) come to mind.

[Nancy]

Holy crap! Um...no pun intended...that would be awful! It sounds like your pool people and my pool people are in agreement. Nancy :-)

[domanova]

Once a year should be more than enough, unless you are lax about maintaining the chlorine level. We have a salt system chlorinator, so the chlorine is always adequate. At one point last summer I had let the stabilzer get too low, so I both added stabilizer and superchlorinated. Over the past 4 years that's the only time I've "shocked" the pool, and it has no algea. On the other hand, once a week is really good for business!

[Richard J Kinch]

This is no doubt because they are selling you *cyanurated chlorine*, which doesn't disinfect well. You need to superchlorinate because all that money you're spending on "chlorine" (cyanurates, actually--read the label) isn't providing much ORP after you load up the water with "stabilizer" [sic, cyanurates again] that spoils the chlorine's effectiveness. It's basically a formula to get you in the store regularly.

This method of chlorination is typically not permitted for public pools because it so ineffective. But it satisfies the clueless pool owner.

The pools store's "computerized" tests [sic, kid with reagents typing results into an outdated computer program designed to sell you more stuff] *do not* test for ORP, they test for free chlorine, which is invalid for cyanurated pools. Same for test kits you buy.

Chlorine per se is nothing, ORP is everything.

See my discussion at the end of this page:

[Paul Giroux]

Once at the start of the season and once when closing it. Other that that I have the chemistry balanced when I open it in the spring (TA, hardness, pH), put chlorine in it every night and keep it clean and vacumed, check the skimmers and the pump filter. It gets to be routine for me.

I close it as late as possible and keep it clean until the very end (use two nets, one for the winter, and one for leaves, on top), and spring opening is a breeze.

Just opened mine last weekend.

[SueMarkP]

I read your web page a long time ago, and should have read it again as it answers a lot of my questions. I know you're anti cyanuric, but I'm not about to bite off a project to dose chlorine without stabilizer. I try to keep the cyanuric acid as low as I can, and boost things with calcium hypochlorite as needed (excessive sun or swimmers). At least I'm not shocking with stabilized chlorine....

I may go buy an ORP meter, as that seems like the true test of sanitizer effectiveness. Although I may not know what I'm getting into as far as keeping it calibrated and changing its electrodes.