Can I use household bleach for chlorine?

[dianam]

Is household bleach the same as the chlorine from the pool store?

[scotty5x5]

In some ways it's better. The Cal Hypo from the pool store adds calcium each time you use it and it can build up. The Tri chlor and Di chlor add stabilizer which can build up. Bleach doesn't build up anything but a little salt. The only problems I have with bleach is lugging the bottles home and they have raised the prices lately so I don't really know how it compares with a tub of chlorine from the pool store. I don't shock with it anymore because of that but use it for routine chlorine levels.
Scott

[CarlD]

Laundry bleach (regular unscented or ultra unscented) uses Sodium Hypochlorite as the active ingredient, either 5.25% or 6%. The rest is "inert" ingredients--basically salt water.

If you go to the pool store and buy "liquid chlorine" in either gallon jugs or blue carboys you will be getting the same thing: Sodium Hypochlorite solution. Sometimes it will be 6% (exactly the same as Ultra bleach) or 10% or 12.5% (which is really 10% because it breaks down SO quickly).

Sometimes they call it "Liquid Shock" when it's 12.5%.

But the bottom line is that it is EXACTLY the same stuff as laundry bleach with a different label, and maybe a stronger concentration. Caveat: Pool store guys will tell you if you use liquid chlorine you MUST add muriatic acid to compensate. Do NOT believe them. Test your pH and add acid only if pH is high. You rarely will using bleach/liquid chlorine.

Dry pool store chlorine can not only be calcium based (Cal-hypo), it can also be di-chlor or tri-chlor. Cal-hypo adds calcium-which concrete pool owners need (up to a limit--400ppm), but vinyl pool owners don't (although pool store guys will swear on their saintly mother's head that you do--they are either honestly wrong or lying).

Di-Chlor and Tri-Chlor both add stabilizer--Cyanuric Acid or CYA. You need some but too much is a BIG problem. They are also extremely acidic and will lower your pH--whether you want them to or not.

Finally there's a lithium chlorine powder. It costs a fortune, has very little active chlorine and may have unexpected effects--I don't know what concentrations of lithium do in water.

Bottom line: Most of us use laundry bleach to chlorinate. I do.

[dianam]

So what do you use to shock with then?

[xoroniox]

bleach is for shocking, shocking just means that you are bringing the level of chlorine in your water to a higher concentration. example if 3ppm is normal for you than 15ppm could be your shock level, just add more bleach look @ bens best guess cya table to determine your free chlorine and shock levels.

[Sherra]

So what do you use to shock with then?

Bleach. "Shock" is an action, not an item (although there are items labeled "shock", but the whole purpose is to still bring your chlorine level up to a certain level...what's called "break point". Break point will depend on your CYA level. As previously mentioned. See the thread called "Ben's Best Guess CYA Chart" for recommended chlorine levels.

[CarlD]

"Shock" is a verb that means raise chlorine levels high enough to kill anything living in the water, and metabolize all organic compounds. That's ALL it means. Chemicals called "shock" is a mis-nomer designed to fool you, the consumer, into thinking it's more than it is--namely some sort of chlorinating chemical.

To shock you add more chlorine, and it doesn't matter what the source of that chlorine is. Since I use bleach to chlorinate, I use bleach to shock--just a lot more of it.

It's VERY easy to calculate how much bleach to use. You need to know:
1) The volume of your pool in gallons (liters is OK, but then you measure the bleach in liters as well).
2) Your current Free-Chlorine (FC) level
3) Your level of stabilizer/CYA
4) Your shocking level of Free Chlorine which is based solely on your stabilizer level (see the Best Guess table).

You subtract your current FC from your shock-level FC and that tells you how much more FC you need.

Then you either use MWSmith2's Bleach calculator program to tell you how much to use, or you use the formula:

(1,000,000/pool volume) * (bleach concentration) * (gallons of bleach) = FC added

Or you can use the rule of thumb and guessitmate off of it:
1 gallon of regular bleach (5.25%) adds EXACTLY 5.25ppm of FC to 10,000 gallons of water. You need twice as much for 20,000 gallons OR to increase 10,000 gallons by 10.5ppm

1 gallon of Ultra bleach (6%) adds EXACTLY 6ppm of FC to 10,000 gallons,
A 3 quart jug of Ultra adds 4.5ppm of FC to 10,000 gallons.
etc.

For example:
Say your pool has 20,000 gallons
and your CYA is 40ppm
and your current FC is 4.5ppm.

At CYA=40, the correct shock level (from the best-guess table) is 15ppm.

That means you need 10.5ppm MORE of FC to shock your pool.

Well, since 1 gallon of 5.25% adds 5.25ppm to 10,000 gallons, you need 4 gallons of regular bleach to get to 15ppm.

That's all there is to it!

But that's why we ALWAYS want to know the gallonage, the current FC and the current CYA before telling you how much bleach to use.

[waterbear]

Finally there's a lithium chlorine powder. It costs a fortune, has very little active chlorine and may have unexpected effects--I don't know what concentrations of lithium do in water.

Bottom line: Most of us use laundry bleach to chlorinate. I do.

Lithium ions in the water act pretty much the same way sodium ions do....not much effect at all. That is the main plus (along with it's almost instantaneous dissolving) to lithium hypochlorite. The expen$e is the bigge$t minu$.