Bleach or Shock?

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
calamtykelagain

Bleach or Shock?

Postby calamtykelagain » Thu 17 May, 2007 14:44

Pool cover fell into the pool this year, so we opened to a big of a mess and a lot of frogs! They are slowly floating to the surface along with leaves as I've been adding both Dichlor (from Sam's club) and "sock it" (Walmart) through the skimmer while it's on recirculate, so it's bypassing the filter at this point, until I can get the chlorine levels up, since with this much debris, I'd be backwashing every 1/2 hour.

My question is this. I have seen many posts on here about shocking with bleach to open. So far, between yesterday and today I have dumped 29 bags of di and tri shock into it and my chlorine level is still undetectable! YIKES!

So my question is, now that I'm out of both kinds of shocks and going to the store tomorrow, what do I need to get? I have a vinyl liner inground pool with a very old liner so draining would not be a good idea at this point. This happened one other year and the pool store sold me some really expensive Lithium type shock - I'm not sure if it did anything but it was sure expensive, so I don't want to go back and ask them!

Right now the water is completely green/blue but I think a lot of the debris is finally getting out between vaccuuming to waste and floating to the surface. There is a white/brown film on top, similar to what everyone else is describing. (I believe it's from the bleach, probably oxidizing the bacteria, etc. in the water.) I did add some Algae 60, but I've had this foam other years and eventually it goes away. Right now my concern is getting this chlorine level up high enough and long enough to kill the algae!

So should I be using bleach, or would it take a truckload at this point to bring it up to a 10-15PPM?


me_too

Re: Bleach or Shock?

Postby me_too » Thu 17 May, 2007 15:13

calamtykelagain wrote:Pool cover fell into the pool this year, so we opened to a big of a mess and a lot of frogs! They are slowly floating to the surface along with leaves as I've been adding both Dichlor (from Sam's club) and "sock it" (Walmart) through the skimmer while it's on recirculate, so it's bypassing the filter at this point, until I can get the chlorine levels up, since with this much debris, I'd be backwashing every 1/2 hour.

My question is this. I have seen many posts on here about shocking with bleach to open. So far, between yesterday and today I have dumped 29 bags of di and tri shock into it and my chlorine level is still undetectable! YIKES!

So my question is, now that I'm out of both kinds of shocks and going to the store tomorrow, what do I need to get? I have a vinyl liner inground pool with a very old liner so draining would not be a good idea at this point. This happened one other year and the pool store sold me some really expensive Lithium type shock - I'm not sure if it did anything but it was sure expensive, so I don't want to go back and ask them!

Right now the water is completely green/blue but I think a lot of the debris is finally getting out between vaccuuming to waste and floating to the surface. There is a white/brown film on top, similar to what everyone else is describing. (I believe it's from the bleach, probably oxidizing the bacteria, etc. in the water.) I did add some Algae 60, but I've had this foam other years and eventually it goes away. Right now my concern is getting this chlorine level up high enough and long enough to kill the algae!

So should I be using bleach, or would it take a truckload at this point to bring it up to a 10-15PPM?


Doesn't matter what you use for shock, as long as (a) it's unstabilized chlorine (cal hypo, bleach) and you get enough in there for 15-25 ppm or thereabouts. The actual amount you'll have to use depends on the chlorine concentration (this is written on the product label).

There is no need to add anything else, just chlorine, and lots of it.

Report back with the pool volume and chlorine content of what you have in stock and we'll figure out the quantity.

Best,
calamtykelagain

Re: Bleach or Shock?

Postby calamtykelagain » Thu 17 May, 2007 15:29

Why unstabilized, out of curiousity? I was using the dichlor (stabilized I assume?) because I was afraid of what it might do to the liner in quantity (I do use calcium hypo. during the pool season for just regular chlorinating, dissolving it before I add it) I guess since I'm adding through the skimmer and bypassing the filter, it doesn't much matter?

Just wondering what the difference is as far as effectiveness.
OH - It's an inground, 30,000 (?) gallon pool. It came with the house eight years ago, so we never knew the exact specs, but the first year the pool store came out here to start it up for us, they said it looked like that size or thereabouts.
Thanks for the tip - will check back!
kel
me_too

Re: Bleach or Shock?

Postby me_too » Fri 18 May, 2007 13:00

calamtykelagain wrote:Why unstabilized, out of curiousity? I was using the dichlor (stabilized I assume?) because I was afraid of what it might do to the liner in quantity (I do use calcium hypo. during the pool season for just regular chlorinating, dissolving it before I add it) I guess since I'm adding through the skimmer and bypassing the filter, it doesn't much matter?

Just wondering what the difference is as far as effectiveness.
OH - It's an inground, 30,000 (?) gallon pool. It came with the house eight years ago, so we never knew the exact specs, but the first year the pool store came out here to start it up for us, they said it looked like that size or thereabouts.
Thanks for the tip - will check back!
kel


Well the dichlor does add stabilizer to the water, it's about 57% stabilizer, and this may be okay if you're starting with a low level and plan on using a non-stabilized chlorine during the season. It's not a good thing if you're using say trichlor as both these products will add stabilizer to the water and past a certain level (some say 75 some say 100 some say 150 ppm) you'll get lower effectiveness from the chlorine.

As far as effectiveness, from an available chlorine content point of view you can get cal-hypo at anything from 40% to 75% available chlorine, and dichlor is about 64% available chlorine, so it depends on what strength cal-hypo you have.

A better method of dispensing the chlorine would be to dissolve the product in a pail full of hot water instead of pouring it down the skimmer and it saves on equipment wear.
strongisland

Bleach or Shock?

Postby strongisland » Sun 20 Jun, 2010 08:36

you need to test for phosphates and nitrates.
chem geek
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Bleach or Shock?

Postby chem geek » Sun 20 Jun, 2010 19:31

strongisland wrote:you need to test for phosphates and nitrates.

Chlorine alone is able to kill algae faster than it can grow, even at very high phosphate and nitrate levels. I have over 3000 ppb phosphates in my pool, yet it remains algae free because I keep the Free Chlorine (FC) level at least 7.5% of the Cyanuric Acid (CYA) level. Algae is limited in its growth rate by sunlight and temperature regardless of how many phosphates or nitrates there are. Yes, one can use phosphate removers to take the edge off of algae growth, in the same way one can use PolyQuat 60 algaecide, but it isn't necessary and is extra cost.

Read the Pool School for more info on maintaining a pool using chlorine alone without the need for algaecides, phosphate removers, clarifiers, flocculants, weekly shocking, etc.

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