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Ph Level Alkalinity And Cya


styro

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I have started more then week ago with lowering my PH level.

At the beginning PH was 8.0.My Alka was 140.

I start adding every evening 20g PH- and my PH level was going down to 7.8

and next evening again back to 8.0.

So far I got my alkalinity around 73 and my PH level just bounce to 7.8( some improvement) no more 8.

I'm just wondering how much lower I have to go down with my Alkalinity to get the PH stable at 7.6? and How much is safe 60 or less for alkalinity?.From test straps you can tell 80-120 is safe.

When I reach PH level 7.6 I just have to maintain alkalinity at the same level adding (alkariser or PH-)?

My other question is about CYA.

My dealer told me not to wary about Cyanuric Acid since is a SPA, but from forum I'm founding people talking about CYA to be at around 30.I know also my spa is not expose to sunlight a specially winter time.So maybe I want need it.

Please help me to solve this puzzle ;) .

Thanks

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7.8 is fine. If you want a lower pH, then you have to lower your alkalinity. You should put your alkalinity wherever it keeps your pH where you want it.

Does the tub contain any plaster or grout?

What is the calcium level?

Cyanuric acid does protect the chlorine from sunlight degradation. It also creates a reserve of chlorine that is released as chlorine is used up. Therefore, it helps maintain steady levels under varying conditions.

Furthermore, cyanuric acid moderates the reaction rate of chlorine, which helps reduce excessive oxidation.

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7.8 is fine. If you want a lower pH, then you have to lower your alkalinity. You should put your alkalinity wherever it keeps your pH where you want it.

Does the tub contain any plaster or grout?

What is the calcium level?

Cyanuric acid does protect the chlorine from sunlight degradation. It also creates a reserve of chlorine that is released as chlorine is used up. Therefore, it helps maintain steady levels under varying conditions.

Furthermore, cyanuric acid moderates the reaction rate of chlorine, which helps reduce excessive oxidation.

Hi,

My spa is new Neptune series Trident 2009 does mot have plaster or grout it is made from acrylic.

Calcium level is 157.

If I do need CYA then how much and what to add and when?

Today's test:

F CH - 2.2

T CH - 3.4

PH -7.8

TA - 73

CH - 157

CYA -0

Thanks for help

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With a calcium level of about 160, you would be better with a pH of about 7.6. Go to thepoolcalculator.com to calculate your Calcite Saturation Index.

You want to keep your index slightly negative to prevent scaling. About -0.1 to -0.3.

Cyanuric acid can be adding by using dichlor to chlorinate until the cyanuric acid level reaches about 20 to 30 ppm.

The thepoolcalculator.com has a feature that can tell you the effect of adding different chemicals, such as dichlor.

Since you have some combined chlorine ( 3.4 - 2.2 = 1.2 ppm), you need to shock with bleach or MPS.

You may also want to consider adding 30 to 50 ppm borates (From boric acid or Borax) to help stabilize your pH.

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With a calcium level of about 160, you would be better with a pH of about 7.6. Go to thepoolcalculator.com to calculate your Calcite Saturation Index.

You want to keep your index slightly negative to prevent scaling. About -0.1 to -0.3.

Cyanuric acid can be adding by using dichlor to chlorinate until the cyanuric acid level reaches about 20 to 30 ppm.

The thepoolcalculator.com has a feature that can tell you the effect of adding different chemicals, such as dichlor.

Since you have some combined chlorine ( 3.4 - 2.2 = 1.2 ppm), you need to shock with bleach or MPS.

You may also want to consider adding 30 to 50 ppm borates (From boric acid or Borax) to help stabilize your pH.

I just want to add ,I do have ozonator and is set to run 2 times 1 h a day.

I use a Lithium as a chlorine sanitizers so I don't know if bleach or MPS will go ok with lithium.

What should look for in the store any brand (bleach or MPS?)

What is a MPS?

Thanks

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Bleach (and chlorinating liquid) is sodium hypochlorite. Lithium chlorine sanitizer is lithium hypochlorite. They are virtually identical except that the lithium is in powdered form and more concentrated so you use less by weight, BUT even accounting for that it is still at least 5-6 times more expensive. The only reason to use lithium over bleach would be if you were worried about spilling the bleach onto your clothes since, being a liquid, it's easier to spill.

The best bleach to use is Clorox Regular unscented bleach that should say "6% Sodium hypochlorite" on the bottle and also probably says "5.7% Available Chlorine" since it is registered with the EPA as a sanitizer/disinfectant for pools (they didn't bother to register for spas since the volume is so much lower).

MPS is non-chlorine shock with the main ingredient potassium monopersulfate (aka potassium peroxymonosulfate) usually at 43% strength.

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Here are the ingredients of Lithium hypochlorite from an MSDS.

Lithium Hypochlorite, dry 25-30 %

Sodium chloride 36 %

Sodium sulfate anhydrous 13 %

Potassium bisulfate 6 %

Lithium chloride 4 %

Lithium carbonate 2 %

Lithium hydroxide 1 %

Water 4-9 %

Lithium Chlorate 2 %

Lithium carbonate is even less soluble than calcium carbonate. I would begin to have some concern about lithium carbonate scale after using lithium hypochlorite for extended periods. Although, I am not sure at what point it would become an issue. Most likely, it would not be a problem for most people.

I think that bleach is a better alternative.

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Here are the ingredients of Lithium hypochlorite from an MSDS.

Lithium Hypochlorite, dry 25-30 %

Sodium chloride 36 %

Sodium sulfate anhydrous 13 %

Potassium bisulfate 6 %

Lithium chloride 4 %

Lithium carbonate 2 %

Lithium hydroxide 1 %

Water 4-9 %

Lithium Chlorate 2 %

Lithium carbonate is even less soluble than calcium carbonate. I would begin to have some concern about lithium carbonate scale after using lithium hypochlorite for extended periods. Although, I am not sure at what point it would become an issue. Most likely, it would not be a problem for most people.

I think that bleach is a better alternative.

Hi there,

Thanks for all advise.

I was hoping since I'm new this forum and I'm newbie to whole SPA chemistry if someone summarize and tell me what to use.I'm very confused right now.

The main thing I have a lot of Lithium as a sanitizer will last me at list for 1.5 year.

So I have to use it.

After reading the Nitro's Approach To Water Maintenance, A guide to water balance and sanitation

I decide to Lower my PH and try to keep at level closed to 7.6.

My alkalinity is going down.

My numbers from todays reading:

F.ch-3.8

T.ch-5.36

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Here are the ingredients of Lithium hypochlorite from an MSDS.

Lithium Hypochlorite, dry 25-30 %

Sodium chloride 36 %

Sodium sulfate anhydrous 13 %

Potassium bisulfate 6 %

Lithium chloride 4 %

Lithium carbonate 2 %

Lithium hydroxide 1 %

Water 4-9 %

Lithium Chlorate 2 %

Lithium carbonate is even less soluble than calcium carbonate. I would begin to have some concern about lithium carbonate scale after using lithium hypochlorite for extended periods. Although, I am not sure at what point it would become an issue. Most likely, it would not be a problem for most people.

I think that bleach is a better alternative.

Hi there,

Thanks for all advise.

I was hoping since I'm new this forum and I'm newbie to whole SPA chemistry if someone summarize and tell me what to use.I'm very confused right now.

The main thing I have a lot of Lithium as a sanitizer will last me at list for 1.5 year.

So I have to use it.

After reading the Nitro's Approach To Water Maintenance, A guide to water balance and sanitation

I decide to Lower my PH and try to keep at level closed to 7.6.

My alkalinity is going down.

My numbers from todays reading:

F.ch-3.8

T.ch-5.36

PH-7.9

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Here are the ingredients of Lithium hypochlorite from an MSDS.

Lithium Hypochlorite, dry 25-30 %

Sodium chloride 36 %

Sodium sulfate anhydrous 13 %

Potassium bisulfate 6 %

Lithium chloride 4 %

Lithium carbonate 2 %

Lithium hydroxide 1 %

Water 4-9 %

Lithium Chlorate 2 %

Lithium carbonate is even less soluble than calcium carbonate. I would begin to have some concern about lithium carbonate scale after using lithium hypochlorite for extended periods. Although, I am not sure at what point it would become an issue. Most likely, it would not be a problem for most people.

I think that bleach is a better alternative.

Hi there,

Thanks for all advise.

I was hoping since I'm new this forum and I'm newbie to whole SPA chemistry if someone summarize and tell me what to use.I'm very confused right now.

The main thing I have a lot of Lithium as a sanitizer will last me at list for 1.5 year.

So I have to use it.

After reading the Nitro's Approach To Water Maintenance, A guide to water balance and sanitation

I decide to Lower my PH and try to keep at level closed to 7.6.

My alkalinity is going down.

My numbers from today's reading:

F.ch-3.8

T.ch-5.36

PH-7.9

Alka-72

CH-157

CYA-0

I'm adding around 15-25g Lithium after each use depense from load.

My question will be about alkalinity: since is close to 70 wont' be corrosive water to my spa ??

The perfect number is between 80 and 120.

My second question is do I need to focus on PH to lower and keep at 7.6 and under and let alkalinity go down whatever will takes to maintain ph or just focus on saturation level and How to accomplish that level?????

please tell me If I need CYA at all and what product to use according I'm going to use my Lithium for a Year.

Thanks in advance.

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Just lower your pH to 7.6 using acid. Allow the alkalinity to go where it wants as long as your pH remains stable. Your alkalinity will probably need to go to about 60. The 80 to 120 range is just a guide; it is not necessary.

A low Saturation Index is not much of a concern with an all-plastic hot tub. Try not to go much below -0.3 just to be safe. A high Saturation Index can cause scaling in any pool or hot tub. Especially in a heater or salt cell where high temperatures and high pH can significantly increase the local CSI.

The Saturation Index is specifically for Calcium Carbonate (Calcite).

As I noted above, Lithium Carbonate is even less soluble than calcium carbonate. I do not know at what point lithium carbonate scaling would become a problem, if at all. I am just speculating based on the low solubility. I would think that the primary risk from scale would be due to several of the following conditions:

1) Extended use of only Lithium hypochlorite, which would increase the lithium concentration,

2) High pH.

3) High carbonate levels (From high pH and high carbonate alkalinity).

4) Use of lithium hypochlorite immediately after adding sodium carbonate.

I recommend the moderate use of lithium. I suggest that you use some dichlor to add cyanuric acid to about 20 to 30 ppm, and that you use bleach on a regular basis. You do not NEED to use Lithium hypochlorite exclusively just because you have a lot of it.

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Just lower your pH to 7.6 using acid. Allow the alkalinity to go where it wants as long as your pH remains stable. Your alkalinity will probably need to go to about 60. The 80 to 120 range is just a guide; it is not necessary.

A low Saturation Index is not much of a concern with an all-plastic hot tub. Try not to go much below -0.3 just to be safe. A high Saturation Index can cause scaling in any pool or hot tub. Especially in a heater or salt cell where high temperatures and high pH can significantly increase the local CSI.

The Saturation Index is specifically for Calcium Carbonate (Calcite).

As I noted above, Lithium Carbonate is even less soluble than calcium carbonate. I do not know at what point lithium carbonate scaling would become a problem, if at all. I am just speculating based on the low solubility. I would think that the primary risk from scale would be due to several of the following conditions:

1) Extended use of only Lithium hypochlorite, which would increase the lithium concentration,

2) High pH.

3) High carbonate levels (From high pH and high carbonate alkalinity).

4) Use of lithium hypochlorite immediately after adding sodium carbonate.

I recommend the moderate use of lithium. I suggest that you use some dichlor to add cyanuric acid to about 20 to 30 ppm, and that you use bleach on a regular basis. You do not NEED to use Lithium hypochlorite exclusively just because you have a lot of it.

Thanks for all advise.

By using bleach on regular basis when I'm going to use Lithium?Can I use both at the same time to keep level of chlorine accurate?To switch to bleach should I drain the spa complete.What about Dichloro granular (have no effect on PH and alkalinity) won't be a better option?

Thanks

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Thanks for all advise.

By using bleach on regular basis when I'm going to use Lithium?Can I use both at the same time to keep level of chlorine accurate?To switch to bleach should I drain the spa complete.What about Dichloro granular (have no effect on PH and alkalinity) won't be a better option?

Thanks

Bleach, lithium hypochlorite and dichlor are all sources of chlorine. There is no need to use more than one. I see two options:

1) Continue using lithium hypochlorite (since you have already paid for it) -or-

2) Stop using lithium hypochlorite for the reasons mentioned above. Use dichlor until you add approx 30-35 ppm free chlorine to build up your cyanuric acid to ~30 ppm. You need to stop using dichlor at this point to prevent the cyanuric acid concentration from significantly exceeding 30 ppm where chlorine becomes less effective. Switch to bleach. Rule-of-thumb is that you will need to add 5 fluid ounces of 6% unscented bleach (e.g. Clorox) for every person-hour of soaking. This will cost you about $2/month.

You do not need to drain your spa to switch from lithium hypochlorite to the dichlor-then-bleach method.

Useful links: Nitro's Approach to Water Maintenance, The Pool Calculator.

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I think that the lithium is fine to use, especially since you already have it and don't want to waste it. I just suggest that you don't use it exclusively.

As I have previously noted, I don't know that you would have a problem if you used lithium as your only source of chlorine. I am just speculating based on the low solubility of lithium carbonate. It would probably take a while for enough lithium to build up to where you might have a problem.

I recommend that you use some dichlor now, and then alternate between lithium and bleach. Dichlor is slightly acidic, so that will work out well with your currently high pH.

If you do use lithium exclusively, try to watch out for scale buildup. I would also be interested in knowing what results you get if you do use only lithium.

Never add two different chemicals at the same time. Always wait at least an hour between additions of different chemicals.

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I think that the lithium is fine to use, especially since you already have it and don't want to waste it. I just suggest that you don't use it exclusively.

As I have previously noted, I don't know that you would have a problem if you used lithium as your only source of chlorine. I am just speculating based on the low solubility of lithium carbonate. It would probably take a while for enough lithium to build up to where you might have a problem.

I recommend that you use some dichlor now, and then alternate between lithium and bleach. Dichlor is slightly acidic, so that will work out well with your currently high pH.

If you do use lithium exclusively, try to watch out for scale buildup. I would also be interested in knowing what results you get if you do use only lithium.

Never add two different chemicals at the same time. Always wait at least an hour between additions of different chemicals.

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I think that the lithium is fine to use, especially since you already have it and don't want to waste it. I just suggest that you don't use it exclusively.

As I have previously noted, I don't know that you would have a problem if you used lithium as your only source of chlorine. I am just speculating based on the low solubility of lithium carbonate. It would probably take a while for enough lithium to build up to where you might have a problem.

I recommend that you use some dichlor now, and then alternate between lithium and bleach. Dichlor is slightly acidic, so that will work out well with your currently high pH.

If you do use lithium exclusively, try to watch out for scale buildup. I would also be interested in knowing what results you get if you do use only lithium.

Never add two different chemicals at the same time. Always wait at least an hour between additions of different chemicals.

The company I'm buying from they have a product call Spa sanitize-stabilized(dichlor) sanitizer.

I don't know if this is the product, what should I ask for?

From your instruction I need to use dichlor till the CYA will come to 20-30 ppm.

Then I will switch back to lithium and bleach.(every other day?)

I was searching catalog for bleach and have a problem to locate such a product.Bleach is a liquid or powder?

What should I ask for?

Todays numbers are:

F CH 3.67

T CH 3.97

PH 7.9

ALKA 63

CH 167

Thanks

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The company I'm buying from they have a product call Spa sanitize-stabilized(dichlor) sanitizer.

I don't know if this is the product, what should I ask for?

From your instruction I need to use dichlor till the CYA will come to 20-30 ppm.

Then I will switch back to lithium and bleach.(every other day?)

I was searching catalog for bleach and have a problem to locate such a product.Bleach is a liquid or powder?

What should I ask for?

Todays numbers are:

F CH 3.67

T CH 3.97

PH 7.9

ALKA 63

CH 167

Thanks

If it says dichlor, that's the stuff to use.

Alternate lithium and bleach on some schedule you find convenient.

Regarding finding bleach... it is a liquid. Pool stores sometimes carry it as "liquid chlorine" with a concentration of 10% or 12.5% sodium hypochlorite. Where are from? I see it in the laundry section of my grocery store, Clorox is the most well-known and reliable brand. Grocery-store bleach will probably be 5% or 6% sodium hypochlorite, sometimes less.

--paulr

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If you use a brand other than Clorox, then get the "Ultra" bleach since that is more likely to be 6% as is Clorox Regular. Off-brand "Regular" bleach is often 3% or less and has a lot of excess lye in it which will tend to raise the pH over time.

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Maintain a consistent 1 to 4 ppm of free chlorine and maintain a 0.0 combined chlorine.

If the free chlorine goes below 1.0, or there are any chloramines, it is important to shock to about 10 ppm. Don't reenter the water until all of the combined chlorine is gone and the free chlorine is 5.0 ppm or less.

Test at least daily until you get very familiar with the particular character of your tub's chemistry. Then you can decide on the optimal testing schedule.

Start with dichlor until you reach 20 to 30 ppm of cyanuric acid and then switch to bleach and lithium.

Once you get some cyanuric acid in the water, maintain a 2 to 5 ppm chlorine level.

I suggest that you alternate between bleach and lithium to make sure that you don't add too much lithium. Add chlorine as needed based on your test results. Chlorine demand will depend on several factors, such as water temperature and usage.

fact_bleach2.jpg

Bleach.

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Maintain a consistent 1 to 4 ppm of free chlorine and maintain a 0.0 combined chlorine.

If the free chlorine goes below 1.0, or there are any chloramines, it is important to shock to about 10 ppm. Don't reenter the water until all of the combined chlorine is gone and the free chlorine is 5.0 ppm or less.

Test at least daily until you get very familiar with the particular character of your tub's chemistry. Then you can decide on the optimal testing schedule.

Start with dichlor until you reach 20 to 30 ppm of cyanuric acid and then switch to bleach and lithium.

Once you get some cyanuric acid in the water, maintain a 2 to 5 ppm chlorine level.

I suggest that you alternate between bleach and lithium to make sure that you don't add too much lithium. Add chlorine as needed based on your test results. Chlorine demand will depend on several factors, such as water temperature and usage.

fact_bleach2.jpg

Bleach.

Thanks for all suggestions.

I will follow and let you know how it goes.

Maintain a consistent 1 to 4 ppm of free chlorine and maintain a 0.0 combined chlorine.

Wat to do if free chlorine and Total chlorine is out of focus?

Not anymore same or very close. F.Ch 2 and T.CH 4

Thanks

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Your total chlorine is 4 and your free chlorine is 2. That means that your combined chlorine is 2. You need to shock by adding chlorine to 10 ppm. For a 400 gallon tub, you would add 9 ounces of bleach.

Once you get some cyanuric acid in the water, maintain a 2 to 5 ppm chlorine level.

I think that you would do best with a pH of about 7.5. Hypochlorous acid is a weak acid with a pKa of about 7.5. That means that it is half hypochlorous acid and half hypochlorite ion at a pH of 7.5.

As the pH increases, the percentage of hypochlorous acid decreases and the percentage of hypochlorite ion increases. Hypochlorous acid is the effective sanitizer. Hypochlorite ions are not good sanitizers.

pH.........Hypochlorous acid........Hypochlorite ion

7.4.................56 %..............................44 %

7.5.................50 %..............................50 %

7.6.................44 %................ .............56 %

7.7................ 39 %..............................61 %

7.8.................33 %..............................67 %

7.9.................28 %..............................72 %

8.0.................24 %.............................76 %

8.1.................20 %.............................80 %

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F CH - 2.2

T CH - 3.4

F CH - 2.2

T CH - 3.4

PH -7.8

TA - 73

CH - 157

CYA -0

F.ch-3.8

T.ch-5.36

F CH 3.67

T CH 3.97

PH 7.9

ALKA 63

CH 167

Styro, how are you testing your water? The level of accuracy that you are reporting is unusual.

Hi,

I replace the water recently a week ago and the last numbers are from the new refill last week

F.ch 3.67

T.ch 3.97

PH 7.9

Alka 63

CH 167

Last night numbers are:

F.ch 1.82

T.ch 2.02

PH 7.8

Alka 62

CH 139

Like you notice my CH went down almost 30 points.

I'm just wondering way?It will always fluctuate or should stay same till next refill?

I just added recently ph- to lower ph its that will effect my hardness?

I do my test with ColorQ+ digital tester and it is excellent and accurate.

Also like you've notice my FCH and TCH almost same.

I think that's the way to keep.Hypochlorous acid mention by quantumchromodyn it is another type of chlorine or ph maintaining(thats the name) I should look in the store or will come under different name?

So many question.

Thanks in advance.

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Hypochlorous acid (HOCl) is the form of chlorine that all chlorine sources create. It is not a product you buy.

As the pH rises, some of the hypochlorous acid molecules lose their hydrogen ions and become hypochlorite ions.

HOCl --> OCl- + H+

The hypochlorite ion is not as effective as the hypochlorous molecule. When the water contains some cyanuric acid, there are fewer problems with higher pH. So, it's less of an issue.

Furthermore, as the hypochlorous acid is used up, the hypochlorite ions turn into hypochlorous acid because they maintain the same ratio.

For example, at a pH of 7.5, half of the chlorine is hypochlorous acid and half is hypochlorite ions. As two hypochlorous acid molecules are used up (reduced), one hypochlorite ion becomes a hypochlorous acid molecule.

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CH 167

...

CH 139

Like you notice my CH went down almost 30 points.

I'm just wondering way?It will always fluctuate or should stay same till next refill?

I just added recently ph- to lower ph its that will effect my hardness?

CH (calcium hardness) should be stable until the next fill, unless you use calcium hypochlorite powder as a chlorine source, or do something else that adds calcium. pH Minus will not affect hardness.

--paulr

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