Bleach Shock For Chlorine System?

[McAli]

Hi all~

I am filling up our new spa for the first time tomorrow, (Artesian Resort 840L 475 Gallon) and was reading the pamphlets for the start-up chemicals (Leisure time) we got.

I think we're going to go with a cholrine sanitizer system because Bromine just seems like a huge pain in the a$$ for maintenace. My question is: Is there a cheaper way to shock our spa? Can we use just plain old household bleach? Not be be a cheap-o, but thats stuff is expensive!

Thanks in advance...

[Chas]

Can we use just plain old household bleach?

No.

Household bleach is Sodium Hypochlorite, has a pH of around 11 give-or-take, so you would have to add the bleach and then immediately add some dry acid - aka "Spa Down" or similar - and that is not only more money, but more hassle. And, it tends to be very low in concentration, which means that you have to add more to get any effect, and while you are doing that you are adding TDS -aka "stuff" - to the water.

So if you want to do the least expensive shock, simply use Dichlor. Two dry ounces should do a good job on a clean tub up to about 500 gallons, but measure the chlorine level with your test strips or test kit at least four hours later to see if the deed got done. If there is not a very high reading of chlorine four hours later you should add another ounce. Leave the lid open and run the jets for at least twenty minutes whenever you do a Dichlor shock.

BTW - there is a difference in the way MPS and Dichlor works. The Dichlor will do a fine shock, but it will smell like chlorine - surprise - and will stick around for a day or two. The MPS is odor-free and goes away in minutes.

I would ONLY use Dichlor for the very first shock on a new spa anyway, because you need the 'thermonucular bomb-blast' effect that only Dichlor can give. You are cleansing the new tub of stale water and road dust and general grime - you want the most kick-butt additive you can get and that would be Dichlor.

Modified my post - I was thinking of pool chlorine. It is different - thanks for the note below.

[McAli]

Chas~

Thank you so much! This forum has been fantastic! So many knowledgeable people...

Thanks again!

-A

[New NW tub owner]

No.

Household bleach is Calcium Hypochlorite, and since it is calcium-based, you can have trouble with calcium buildup. It also has a pH of around 12.8 give-or-take, so you would have to add the bleach and then immediately add some dry acid - aka "Spa Down" or similar - and that is not only more money, but more hassle. And, it tends to be very low in concentration, which means that you have to add more to get any effect, and while you are doing that you are adding TDS -aka "stuff" - to the water.

So if you want to do the least expensive shock, simply use Dichlor. Two dry ounces should do a good job on a clean tub up to about 500 gallons, but measure the chlorine level with your test strips or test kit at least four hours later to see if the deed got done. If there is not a very high reading of chlorine four hours later you should add another ounce. Leave the lid open and run the jets for at least twenty minutes whenever you do a Dichlor shock.

BTW - there is a difference in the way MPS and Dichlor works. The Dichlor will do a fine shock, but it will smell like chlorine - surprise - and will stick around for a day or two. The MPS is odor-free and goes away in minutes.

I would ONLY use Dichlor for the very first shock on a new spa anyway, because you need the 'thermonucular bomb-blast' effect that only Dichlor can give. You are cleansing the new tub of stale water and road dust and general grime - you want the most kick-butt additive you can get and that would be Dichlor.

This is wrong. Household bleach is 'sodium hypochlorite' and does not contain any significant amount of calcium. Sodium hypochlorite is frequently used for water disinfection and does a great job. The household stuff is about 6 percent sodium hypochorite. Put in about 3 ounces per 100 gallons. Bleach IS cheap and does a good job. It's only drawback is that it doesn't last as long in the water as other forms of chlorine do. Depending on your conditions, though, it might be okay to use it part of the time. The best thing about bleach is that it doesn't have any 'stabilizer' in it so it doesn't contribute to the buildup of that.. ll

Bleach, like other forms of chlorine, is a good sanitizing agent but is not really a 'shock' . A 'shock' actually breaks down the organic stuff in the water which is not what the chlorine does, at least at the dose level typical in hot tubs. My opinion is that the best spa 'shock' is the GLB Oxy-brite stuff, although the other major brands are okay, too.

Finally, household bleach solution does have a rather high pH but it has a negligible effect on the ph of the large volume of water in a hot tub and is not a neutralizing agent like 'spa up' is. You don't need (or want!) to add acid to the tub with the bleach. Your spa pH will not measurably change after you add bleach in the amounts described above.

[dlynn]

Hi all~

I am filling up our new spa for the first time tomorrow, (Artesian Resort 840L 475 Gallon) and was reading the pamphlets for the start-up chemicals (Leisure time) we got.

I think we're going to go with a cholrine sanitizer system because Bromine just seems like a huge pain in the a$$ for maintenace. My question is: Is there a cheaper way to shock our spa? Can we use just plain old household bleach? Not be be a cheap-o, but thats stuff is expensive!

Thanks in advance...

Do not use Bleach in a Hot Tub. It may void your warranty. Most mfg warn against using bleach. If you get any bleach on the surface it may damage the spa liner or cover. Beach only contains about 6% clorine compared to 62% for Dichlor. Bleach was not made for Spas and Dichlor was.

I would recommend using the non-clorine shock, MPS. You shock the tub to Oxidize and burn up lotions and other gunk. If you shock with Clorine you may have to wait to get the levels down to a safe level to use the tub, sometimes 1-2 days. Clorine is a sanatizer but will oxidize at high levels, problem is you need those lower levels to use the tub.

Spa maintance seems confusing whether using Clorine or Bromine but after a couple a months you will figure it out. By the way Bromine is no more difficult to learn than Clorine and it is less maintance once everything is set up.

[waterbear]

Do not use Bleach in a Hot Tub. It may void your warranty. Most mfg warn against using bleach. If you get any bleach on the surface it may damage the spa liner or cover. Beach only contains about 6% clorine compared to 62% for Dichlor. Bleach was not made for Spas and Dichlor was.

I would recommend using the non-clorine shock, MPS. You shock the tub to Oxidize and burn up lotions and other gunk. If you shock with Clorine you may have to wait to get the levels down to a safe level to use the tub, sometimes 1-2 days. Clorine is a sanatizer but will oxidize at high levels, problem is you need those lower levels to use the tub.

Spa maintance seems confusing whether using Clorine or Bromine but after a couple a months you will figure it out. By the way Bromine is no more difficult to learn than Clorine and it is less maintance once everything is set up.

If you are using a chlorine system then you want to use a non stabilized form of chlorine for shocking and a stabilized form of chorine for santizer if the spa is exposed to sun. If the spa is indoors you want to use only non stabilzied chlorine since the buildup of Cyanuric acid in the water from stabilized chlorine is detrimental.

Also, some State public health departmens are now saying that no form of stabilized chlorine should be used in a hot tub but this makes maintenance very difficult if the spa is exposed to the sun. The purpose of stabilizer is to protect the chlorine from breaking down in sunlight but it also inhibits it's efficiency at killing microorganisms in the water.

There is only one form of stabilized chlorine that should ever be used in a hot tub and that is dichlor. It will cause a slow pH drop with continued use but it's impact on the pH is very small.The other stabilized chlorine, trichlor, is too slow dissolving and acidic to use in a tub.

Any of the non stabilized chlorines are suitable for hot tub use. They are:

Lithium Hypochlorite---very fast dissolving but very very expensive to use. It has a high pH but because of the acidic reaction that occurs when the free chlorine is in the water it's effect on the spa pH is minimal. IT might cause a slight pH rise over time

Calcium Hypochlorite (Cal Hypo)--often sold as 'spa chlorine sanitizer' and 'spa shock'. slow dissolving, can cause the water to cloud, adds calcium (hardenss) to the water and can lead to scaling, especially if your fill water is hard to start with. It has a high pH and will cause the pH in the spa to rise over time.

Sodium hypochlorite (My choice)- - This is liquid chlorine which is available in 12.5%, 10% and 6% strenths in pool supply stores and also in grocery stores as laundry bleach in both 6% (ultra bleach), 5.25% (reglular bleach) and 3% (some of the cheap off brand laundry bleaches so read your labels!). Laundry bleach is an excellent shock, btw! You want the regular, unscented type...no florals,or special additives.

Sodium hypochorite in any of it's forms has a high pH but because of the acidic reaction of the free chlorine in the water the net effect of spa water pH is usually 0! (The chemistry involved is a bit more complicated than just measuring the pH of the chlorine itself. It's a bit involved so I won't go into it here)

For shocking a 400 gallon spa 1 cup of regular laundry bleach will raise your free chlorine to well above 10 ppm (actully, around 15 ppm) so it is more than enough.

MPS, non chlorine shock, is expensive and is actually best used in indoor spas and with bromne systems (although liquid chlorine is actually a more effective and less expnsive shock for bromine systems.) MPS is NOT a sanitizer and should not be used as one...also MPS needs to be used on a REGULAR basis so there is always a residual in the water or you will get the formation of chloramines. MPS will NOT break down choramines and if they form you will need to shock with chlorine to destroy them. Also MPS makes water testing more difficult since it will read as part of your total chlorine reading unless you use a reagent to eliminte the interferace from it in your testing. Taylor Technologies sells a reagent to remove the MPS interfence for their DPD and FAS-DPD chlorine test kits for those who use MPS as a shock.

one final thought on spa sanitation with chlorine. If you do not want to use dichlor as your primary sanitizer AND you spa is exposed to sunlight then you can use a non stabilized form of chlorine (which one doesn' matter) if yo add enough cyanuric acid (stabilizer) to the water to achieve a 30 ppm level. If you do this do NOT use any dichlor but only non stabilzied chorine.

Chlorine levels in a spa should NEVER be below 2 ppm and ideally should be maintained betweeen 4-8 ppm (anything under 10 ppm is safe to be in according to most State health departments). When you shock the spa you should raise your free chlorine levels to at least 12-15 ppm and wait for the level to drop below 10 ppm before entering the spa. This is usually only a matter of hours. Be sure to leave the cover off the spa when you shock it so the ammonia compounds and nitrogen gas can dissapate into the air.

[Stevie]

Do not use Bleach in a Hot Tub. It may void your warranty. Most mfg warn against using bleach. If you get any bleach on the surface it may damage the spa liner or cover. Beach only contains about 6% clorine compared to 62% for Dichlor. Bleach was not made for Spas and Dichlor was.

I would recommend using the non-clorine shock, MPS. You shock the tub to Oxidize and burn up lotions and other gunk. If you shock with Clorine you may have to wait to get the levels down to a safe level to use the tub, sometimes 1-2 days. Clorine is a sanatizer but will oxidize at high levels, problem is you need those lower levels to use the tub.

Spa maintance seems confusing whether using Clorine or Bromine but after a couple a months you will figure it out. By the way Bromine is no more difficult to learn than Clorine and it is less maintance once everything is set up.

Agreed. Bleach should NEVER be used in a spa.

[kateyc61]

Ok Boys and Girls:

I was going to start a thread and ask this...and probably should do it in the chemisty section....but since you are on the subject:

The Spa came with Leisure Time chemicals start up set..allllll kinds of spa up, spa down, bright and glistening , foam down, water clearifier, etc etc..

The place we bought the spa from gave us a one page instruction sheet on start up, and the maintenence schedul is to add a TBS and a half to this size spa, of "Renew" or Potassium peroxymonosulphate to the spa 20 mins before we get in, and circulate.

Is this the "shock"? What exactly is this stuff?

We have the Vision system that sits on the filter and is supposed to reduce the amount of chlorine needed

But we are directed to use the "Spa 56" chlorinating granuals (56% avail chlorine) in addition to the Renew.

The alkalinty and Ph have been perfect the past 2 weeks since we got it, filled it and set it up (needed some spa down)

I've added the spa 56 maybe every other day? (we are using it every day) The watrer is clear and lovely (except for the foam, which has diminished THANK YOU ALL.

Does it sound like I am doing this right? Can somebody tell me what the renew does? I'm confused.

Thank you. Sorry for rambling as always.

[dlynn]

Renew is a Non-Clorine Shock (MPS). Normaly you use it once a week at the rate of 3 TBS per 250 Gal of Water. Some people use MPS daily, but it is an Oxidizer not a Sanatizer and is designed to be used as a Shock. You Oxidize once a week to burn off lotions and gunk. You Sanatize daily.

Ok Boys and Girls:

I was going to start a thread and ask this...and probably should do it in the chemisty section....but since you are on the subject:

The Spa came with Leisure Time chemicals start up set..allllll kinds of spa up, spa down, bright and glistening , foam down, water clearifier, etc etc..

The place we bought the spa from gave us a one page instruction sheet on start up, and the maintenence schedul is to add a TBS and a half to this size spa, of "Renew" or Potassium peroxymonosulphate to the spa 20 mins before we get in, and circulate.

Is this the "shock"? What exactly is this stuff?

We have the Vision system that sits on the filter and is supposed to reduce the amount of chlorine needed

But we are directed to use the "Spa 56" chlorinating granuals (56% avail chlorine) in addition to the Renew.

The alkalinty and Ph have been perfect the past 2 weeks since we got it, filled it and set it up (needed some spa down)

I've added the spa 56 maybe every other day? (we are using it every day) The watrer is clear and lovely (except for the foam, which has diminished THANK YOU ALL.

Does it sound like I am doing this right? Can somebody tell me what the renew does? I'm confused.

Thank you. Sorry for rambling as always.

[Roger]

Using bleach as a sanitizer is not recomended. Houshold bleach is 5 percent chlorine and 95 percent? Well stuff that you don't need in your water. Sodium Dichloro S triazinetrione, or dichlor for short, Spa 56, or several other names is 62% or better available chlorine Instead of a cup or 2 of bleach to shock a couple tablespoons of dichlor will do it.

[New NW tub owner]

Using bleach as a sanitizer is not recomended. Houshold bleach is 5 percent chlorine and 95 percent? Well stuff that you don't need in your water. Sodium Dichloro S triazinetrione, or dichlor for short, Spa 56, or several other names is 62% or better available chlorine Instead of a cup or 2 of bleach to shock a couple tablespoons of dichlor will do it.

Household bleach is used as a sanitizer by millions of people every day all over the world and is excellent for that purpose. Household bleach is about 6 percent sodium hypochlorite (NaOCl). The other 94 percent is ... water. When you add liquid sodium hypochlorite to your tub, you are adding sodium, oxygen, and chorine along with water. Dichlor is chlorine and cyanuric acid. The cyanuric acid 'stabilizer' consists of nitrogen and oxygen and does not break down in the tub. After some period of time, the cyanuric acid concentration in your tub will build up to unhealthy levels and you will need to drain your water and replace it. At present, I use both dichlor and bleach for sanitizing and alternate between them. If you just use bleach, it tends to dissipate too rapidly and over time the sanitizing is not as good. If you use just dichlor, you build up the cyanuric acid quite quickly and the sanitizing degrades. I put in dichlor for a few days and then switch to bleach for a few days and so on and it leaves me with clear water, and no foam. I also put in a little GLB oxy-brite maybe once a week. I don't know of any reason not to use bleach and you could use bleach by itself without any real problems as long as you monitor the chlorine residual closely.

[Roger]

Household bleach is used as a sanitizer by millions of people every day all over the world and is excellent for that purpose. Household bleach is about 6 percent sodium hypochlorite (NaOCl). The other 94 percent is ... water. When you add liquid sodium hypochlorite to your tub, you are adding sodium, oxygen, and chorine along with water. Dichlor is chlorine and cyanuric acid. The cyanuric acid 'stabilizer' consists of nitrogen and oxygen and does not break down in the tub. After some period of time, the cyanuric acid concentration in your tub will build up to unhealthy levels and you will need to drain your water and replace it. At present, I use both dichlor and bleach for sanitizing and alternate between them. If you just use bleach, it tends to dissipate too rapidly and over time the sanitizing is not as good. If you use just dichlor, you build up the cyanuric acid quite quickly and the sanitizing degrades. I put in dichlor for a few days and then switch to bleach for a few days and so on and it leaves me with clear water, and no foam. I also put in a little GLB oxy-brite maybe once a week. I don't know of any reason not to use bleach and you could use bleach by itself without any real problems as long as you monitor the chlorine residual closely.

Show me where you found that the 95% other than chlorine is water. I looked all over for that information and all I found was "inert"

[waterbear]

Show me where you found that the 95% other than chlorine is water. I looked all over for that information and all I found was "inert"

All forms of sodium hypochlorite, whether laundry bleach or liquid pool chlorine are mostly water and some salt (sodium chloride, table salt) that is a byproduct of the manufacturing process. The water and salt are the "inert ingredients". The pH of 11 is because of the sodium hydroxide content that is necessary to keep it stable (otherwiste the chorine would not stay in solution). The salt added to your spa has absolutely no effect (if it did any pool or spa with a salt water chlorine generator would be in trouble and they work just fine!) There is absolutely no reason why you cant use liquid sodium hypochorte, whether laundry bleach or liquid chlorine in your spa. Pool liquid chlorine is approx. twice as stronge but it breaks down much faster on storage. If you are concerned about the pH realize that when the chlorine reacts in the water it produces an acid reaction that is enough to effectively negate the pH of the sodium hypochlorite added so the effect on your spa water pH is minimal. ALL other forms of chlorine (dichlor, cal hypo, litium hypochlorite) have a greater impact on water pH!

There is absolutely no reason why liquid chlorine (sodium hypochlorite) cannot be used in a spa! It is my first choice for shocking. If it is used for normal chlorination and the spa is exposed to sunlight and outdoors then Cyanuric acid (stabilizer) needs to be added to the water to about 30 ppm to protect the chlorine from the sun. If dichlor is used for normal sanitation this is not necessary since dichlor is about half cyanuric acid. This is also the reason that dichlor should NOT be used for shocking since the cyanuric acid will build up too quickly and cause the spa to need to be drained and refilled in a much shorter time than normal (possibly after a few weeks, depending on the amount of dichlor used as shock and how often the spa is shocked). Also be aware that many public health departments are now recommending that dichlor NOT be used in spas and only unstablilized chlorine (sodium hypochlorite, calcium hypochlorite, lithium hypochlorite) be used and that cyanuric acid NOT be added. This does make keeping the chlorine levels high enough a problem unless you check your water daily, however!

[Chas]

Also be aware that many public health departments are now recommending that dichlor NOT be used in spas and only unstablilized chlorine (sodium hypochlorite, calcium hypochlorite, lithium hypochlorite) be used and that cyanuric acid NOT be added. This does make keeping the chlorine levels high enough a problem unless you check your water daily, however!

I will start by saying that I sold my commercial pool route years ago so this could have changed, but I think this is incorrect, or at least not stated properly - at least for my area. Public Health Departments deal with public pools and spas, not home tubs. But in my experience they don't care what type of chlorine you put in a vessel as long as you keep the level of free chlorine up and the level of Cyanuric Acid (stabilizer) down.

If you use Trichlor Tablets in a commercial pool or spa, the Cy Acid will go up very very fast - they are almost half Cyanuric Acid (well over 40%) so you have to change the water often. I have operated many commercial pools with the "Liquidator," a liquid chlorine injector which is fully NSF now - but we also had Tablet feeders just to keep the inspectors happy. We kept one tab sitting on top of the feeder, but with the feeder empty. If the inspector caught us with our chlorine level down he would drop the tab in for us instead of red tagging (closing) the pool and spa.

Most commercial pools and spas do require checking more than once per week - I had some I visited three times each week.

Now back to the home spas this forum is dedicated to: Dichlor works just fine. It tends to keep the pH right were you need it, it has a very high concentration of effective chlorine power, it is easy to store and handle, it is relatively inexpensive (spill liquid bleach once and you wipe out any savings), and since most folks seem to benefit from water changes every four months, the cyanuric acid is a non-issue.

If you want to use bleach, fine - but be very careful with it, and keep an eye on the TDS. You may be making water changes just as often to keep that down.

One more item - the commercial pools and spas I used to care for all had DE filters with backwash valves. Even the ones with recyling systems (DE 'Bags') had a waste valve so I could dump lots of water each time I visited. I would turn on the fill valve as soon as I arrived at any of these pools or spas - in effect I was doing an on-going water change every visit. The Cy Acid levels and or TDS seldom got ahead of me that way.

And that is where I gained my respect for frequent water changes in any spa, even a home tub. Water is still the cheapest 'chemical' you can add to a tub, and unless you live on a well or have other reasons to limit water use, the extra hundred gallons per month is a benefit, not a big problem. And it doesn't even balance an extra five minutes in the shower daily.

[waterbear]

I will start by saying that I sold my commercial pool route years ago so this could have changed, but I think this is incorrect, or at least not stated properly - at least for my area. Public Health Departments deal with public pools and spas, not home tubs. But in my experience they don't care what type of chlorine you put in a vessel as long as you keep the level of free chlorine up and the level of Cyanuric Acid (stabilizer) down.

This has changed in many states. They now say that a hot tub should have NO cya at all!

If you use Trichlor Tablets in a commercial pool or spa, the Cy Acid will go up very very fast - they are almost half Cyanuric Acid (well over 40%) so you have to change the water often. I have operated many commercial pools with the "Liquidator," a liquid chlorine injector which is fully NSF now - but we also had Tablet feeders just to keep the inspectors happy. We kept one tab sitting on top of the feeder, but with the feeder empty. If the inspector caught us with our chlorine level down he would drop the tab in for us instead of red tagging (closing) the pool and spa.

Most commercial pools and spas do require checking more than once per week - I had some I visited three times each week.

Now back to the home spas this forum is dedicated to: Dichlor works just fine. It tends to keep the pH right were you need it, it has a very high concentration of effective chlorine power, it is easy to store and handle, it is relatively inexpensive (spill liquid bleach once and you wipe out any savings), and since most folks seem to benefit from water changes every four months, the cyanuric acid is a non-issue.

If you want to use bleach, fine - but be very careful with it, and keep an eye on the TDS. You may be making water changes just as often to keep that down.

I still think that dichlor is the chlorine of choice for sanitizing but not shocking. Using a non stabilzied chlorine for shocking will keep the cya from rising too fast. It is the high cya levels and NOT TDS that cause the sanitation system to become ineffetive! If high TDS caused chlorine to become ineffective as a sanitizer then any pool or spa with a salt water chlorine genterator would not work properly since their TDS would be the salt level PLUS any other ions in the water! This is not the case, however.

One more item - the commercial pools and spas I used to care for all had DE filters with backwash valves. Even the ones with recyling systems (DE 'Bags') had a waste valve so I could dump lots of water each time I visited. I would turn on the fill valve as soon as I arrived at any of these pools or spas - in effect I was doing an on-going water change every visit. The Cy Acid levels and or TDS seldom got ahead of me that way.

unfortunately, this is not the case with spas and most modern pool installations (cartridge filters are pretty much all you see in spas and have become the most commen type installed in most new pool builds now. Once again I repeat it is not the TDS that causes the problems but the buildup of cya. When only stabilized chlorine is used this happens very fast on these systems.

And that is where I gained my respect for frequent water changes in any spa, even a home tub. Water is still the cheapest 'chemical' you can add to a tub, and unless you live on a well or have other reasons to limit water use, the extra hundred gallons per month is a benefit, not a big problem. And it doesn't even balance an extra five minutes in the shower daily.