Dichlor Or Mps?

[dcp]

Hot tub came with house and now I'm trying to figure out water chemistry/maintenance.

Its a 3 yr old Jacuzzi j-385 (~550gal) with ozonator; usage 2 people for 30mins 2-3 times per week.

I have been recommended two different approaches to regular maintenance:

1 - Tablespoon dichlor after every use; shock w/ MPS once a week.

2 - Tablespoon MPS after every use; shock with dichlor once a week.

Currently I'm checking pH and alkalinity every couple of days and doing #1 above.

Which is better #1 or #2 (or is there a better option #3)?

Also I don't seem to get any free chlorine hang around for more than a day or so. Is that a concern? Seem to recall reading somewhere ozone may break it down - true or not?

[Nitro]

How about #3. Use Dichlor for a week, then switch to bleach. Keep your Free Chlorine (FC) between 3-6 ppm. Never let it drop below 1, and shock once a week to 12. If you do that you'll never need MPS.

However, you can use MPS to help clear Combined Chlorine (spent chlorine), and oxidize waste. This mostly happens when you have high bather loads.

If you want to learn more about this method go here.

[Hillbilly Hot Tub]

Hot tub came with house and now I'm trying to figure out water chemistry/maintenance.

Its a 3 yr old Jacuzzi j-385 (~550gal) with ozonator; usage 2 people for 30mins 2-3 times per week.

I have been recommended two different approaches to regular maintenance:

1 - Tablespoon dichlor after every use; shock w/ MPS once a week.

2 - Tablespoon MPS after every use; shock with dichlor once a week.

Currently I'm checking pH and alkalinity every couple of days and doing #1 above.

Which is better #1 or #2 (or is there a better option #3)?

Also I don't seem to get any free chlorine hang around for more than a day or so. Is that a concern? Seem to recall reading somewhere ozone may break it down - true or not?

The 2nd recipe, MPS at each use and dichlor weekly is only if you are using a mineral stick such as Nature 2, MPS is not a sanitizer. With the Nature 2 you can go as low as a .5 risdual of chlorine. If you choose the "bleach" method, please read up on it. We have seen MANY tubs damaged from using bleach, there are drawbacks to it also.

[Nitro]

We have seen MANY tubs damaged from using bleach, there are drawbacks to it also.

Only because they didn't use Dichlor to build up CYA in the water first. Hence the reason we call it the Dichlor/Beach method, instead of simply the Bleach method. If you add too much acid to your tub, you can damage your tub also. The key is education.

There are drawbacks to everything, including owning a hot tub. But I think before someone makes a decision about their sanitizer, they should know all the facts. The fact is, the Dichlor/Bleach method is the easiest, cheapest and safest method to use.

Also, it should be the first method a beginner uses, so they learn how to properly maintain their tub. Later, if they are having problems (can't handle Chlorine etc.), they can always switch to N2, or even Bromine easily without changing the water. To me it's a no brainer.

[dcp]

Thanks Nitro and Hillbilly

As in many things a lot of misinformation around.

The recommendation to use MPS after use and dichlor weekly did not include using a mineral stick - I think I can rule that option out now.

I'd also been told by a different local hot tub vender/installer to use Trichlor in a floater (based on manual saying don't use trichlor it didn't take much web research to rule that out)

I guess I'm not seeing the advantage of the dichlor/bleach method over just dichlor - it seems way more complicated and prone to testing error.

Unless there's a big problem with just dichlor I think thats the direction I'm headed (my #1) - per Nitro's thread linked above seems the only issue might be building up too much CYA - is that right?

[Hillbilly Hot Tub]

We have seen MANY tubs damaged from using bleach, there are drawbacks to it also.

Only because they didn't use Dichlor to build up CYA in the water first. Hence the reason we call it the Dichlor/Beach method, instead of simply the Bleach method. If you add too much acid to your tub, you can damage your tub also. The key is education.

There are drawbacks to everything, including owning a hot tub. But I think before someone makes a decision about their sanitizer, they should know all the facts. The fact is, the Dichlor/Bleach method is the easiest, cheapest and safest method to use.

Also, it should be the first method a beginner uses, so they learn how to properly maintain their tub. Later, if they are having problems (can't handle Chlorine etc.), they can always switch to N2, or even Bromine easily without changing the water. To me it's a no brainer.

Its not just the CYA, it is also damage due to PH creep, Bleach is high PH, new tubs induce a lot of air, also increasing the PH, result is major scale and damaged tubs. You have to read about and follow the directions very carefully.

This is your opinion, it is no safer or easier than some of the other systems, cheaper....I still thin at the price of bleach an the amount you use, plus the added PH decreaser needed the cost is very close. Bleach will also vois many manufactures warranties, how cheap is that?

I think it may serve a purpose on older tubs with no warranty and very few jets.

[Hillbilly Hot Tub]

Thanks Nitro and Hillbilly

As in many things a lot of misinformation around.

The recommendation to use MPS after use and dichlor weekly did not include using a mineral stick - I think I can rule that option out now.

I'd also been told by a different local hot tub vender/installer to use Trichlor in a floater (based on manual saying don't use trichlor it didn't take much web research to rule that out)

I guess I'm not seeing the advantage of the dichlor/bleach method over just dichlor - it seems way more complicated and prone to testing error.

Unless there's a big problem with just dichlor I think thats the direction I'm headed (my #1) - per Nitro's thread linked above seems the only issue might be building up too much CYA - is that right?

Yes, you have to watch the CYA level. If you shock weekly with MPS, this will help. My customers that use dichlor keep a lower risdual of chlorine, closer to 2 and shock with MPS if the CC gets high, most this is weekly. Using less dichlor = less CYA and a longer period before water changes, just don't let your chlorine level drop to low without the added protection of N2.

[Nitro]

I guess I'm not seeing the advantage of the dichlor/bleach method over just dichlor - it seems way more complicated and prone to testing error.

Unless there's a big problem with just dichlor I think thats the direction I'm headed (my #1) - per Nitro's thread linked above seems the only issue might be building up too much CYA - is that right?

Actually the Dichlor/Bleach method isn't any more complicated then using only Dichlor. However, there is a learning curve to maintaining Hot Tub water in general. Regardless of whether you switch to bleach you still need to learn it. Otherwise, you will have problems.

Every 10 ppm Free Chlorine (FC) you add to your tub using Dichlor, you also add 9 ppm CYA. The ideal range of CYA in a spa is 20-50 ppm. Where the problem comes in is when CYA gets too high 100, 200 etc. As CYA gets higher, your FC become less effective.

For instance; with a CYA = 100 ppm (which can happen in a matter of a few weeks), you would need ~25 ppm FC, just to bring the tub to shock level. With a CYA = 20 ppm, it only takes ~10 ppm FC to shock the tub. I'm sure you can imagine if CYA gets up around 200 ppm.

If the solution to rising CYA was more difficult or costly to solve, I could see staying with Dichlor, using MPS to help out and change your water more often. However, the solution to the rising CYA issue, is actually just as easy, and a lot cheaper then using Dichlor. So to me it's a no brainer.

Just remember, whether you use only Dichlor or switch to bleach, the learning curve is still there. If you don't learn to maintain your water, you will have problems, regardless of the sanitation method.

Lastly, don't be scared off by pH Creep. If your TA is adjusted well, it's not much of a problem.

[Nitro]

Yes, you have to watch the CYA level. If you shock weekly with MPS, this will help. My customers that use dichlor keep a lower risdual of chlorine, closer to 2 and shock with MPS if the CC gets high, most this is weekly. Using less dichlor = less CYA and a longer period before water changes, just don't let your chlorine level drop to low without the added protection of N2.

Which is the main reason why switching to bleach is easier, safer, more foolproof and much cheaper. Not to mention you can go longer between water changes.

[Nitro]

Its not just the CYA, it is also damage due to PH creep, Bleach is high PH, new tubs induce a lot of air, also increasing the PH, result is major scale and damaged tubs. You have to read about and follow the directions very carefully.

pH creep is virtually nonexistent if the TA is low enough, and Borates are added. I've proved that myself. I went three weeks before I changed my water without adding acid. I have yet to add acid (after the initial dose) on this water change (2 weeks later).

This is your opinion, it is no safer or easier than some of the other systems, cheaper....I still thin at the price of bleach an the amount you use, plus the added PH decreaser needed the cost is very close. Bleach will also vois many manufactures warranties, how cheap is that?

There is no possible way a manufacture (or anyone) can determine bleach was used in a hot tub, IF CYA is present. If someone uses bleach with no CYA, then they will have problems. Just like if they use a hot tub with no sanitizer.

I think it may serve a purpose on older tubs with no warranty and very few jets.

Again, not ture. Warranty is a non issue, as long as you have CYA in your tub.

[chem geek]

As one of the people who initially thought of using Dichlor/bleach, I have to say two things. One is that many people use Dichlor-only (i.e. the Vermont/Northman method) without problems. That, of course, doesn't mean that there are no problems, but rather that they are with a subset of such spas. As Hillbilly Hot Tub points out, in situations where MPS is used as a supplemental oxidizer or in other situations where less chlorine is used or the CYA level isn't climbing as fast (or is possibly degrading faster), then the problems associated with higher CYA won't show up simply because the CYA doesn't get that high.

The second point is that there were clearly some tubs with lots of aeration, either from many jets or from use of an ozonator or use of a bleach that was higher in pH (too much excess lye), where the pH rise was a big problem and scaling can occur. Of course, this was before we looked at using an additional pH buffer with Borates (lowering the TA was tried, but didn't help enough). So though Dichlor/Bleach works great for you and for some others, it can cause problems if not done correctly and may be more likely to do so than Dichlor-only in the case of pH drift. See this thread for some people where Dichlor/Bleach didn't work and this thread for an industry person that chewed me out when apparently one user tried it without monitoring pH and had problems, probably scaling. I briefly left the forum and came back in this thread where it is still not clear if Dichlor-only increases the chances of hot tub itch/rash/lung though the indications are that after 1-2 months of Dichlor-only use it might (at least when N2 isn't used).

Regarding warranties, if the warranty explicitly says you can't use bleach or it will void the warranty, then if something does go wrong (even if unrelated to chemistry) and you are asked, then if you tell the truth the manufacturer can refuse to honor the warranty and if you lie then, well, you are lying. Not a good situation to be in. It is unlikely that the manufacturers understand the chemical difference between using bleach-only vs. using Dichlor then bleach.

So offering the method as an alternative that people can try IF they monitor their chemistry and get to a point where things are stable is one thing, but it's obviously more complicated than just using Dichlor alone, even though Dichlor/Bleach has benefits.

Richard

[Nitro]

The second point is that there were clearly some tubs with lots of aeration, either from many jets or from use of an ozonator or use of a bleach that was higher in pH (too much excess lye), where the pH rise was a big problem and scaling can occur. Of course, this was before we looked at using an additional pH buffer with Borates (lowering the TA was tried, but didn't help enough). So though Dichlor/Bleach works great for you and for some others, it can cause problems if not done correctly and may be more likely to do so than Dichlor-only in the case of pH drift. See this thread for some people where Dichlor/Bleach didn't work and this thread for an industry person that chewed me out when apparently one user tried it without monitoring pH and had problems, probably scaling. I briefly left the forum and came back in this thread where it is still not clear if Dichlor-only increases the chances of hot tub itch/rash/lung though the indications are that after 1-2 months of Dichlor-only use it might (at least when N2 isn't used).

My tub has 72 jets with two 4.8 HP motors. It produces a lot of aeration. I have actually tested to see how high pH would rise with my TA at 60 ppm. I ran my jets and air for ~6 hours one day. pH never went above 7.8.

Actually I have read those threads. How do you think I got interested in Dichlor/Beach? However, I believe the FEW people that had pH creep issues blew it way out of proportion. Just curious, did anyone in those threads lower their TA to 50-60?

I think the key may be the Borates though. I have had no pH creep issues at all after adding them. As a matter of fact on the last fill I had more issues with pH being lowered by using MPS. But that was easily fixed be raising TA. However, even before I used Borates, my pH was pretty solid.

Ozone will cause more pH creep. However, at this point I don't believe pH creep can't be solved in any tub. I solved it in mine, and two other friend's tubs. Neither of them have Borates, because I was wanting to see how bad the pH creep. So far they haven't had a problem.

As far as being more complicated. Here's where we disagree. Sure there's an initial step of getting CYA to 20 ppm. But afterward you only need Bleach. With Dichlor Only you have to worry about your CYA level. To cut down on CYA, you need to use less Dichlor and more MPS and/or change water more often etc. To me (and so far everyone who tried it except a select few) it's much easier to switch to bleach and not worry about anything. I can add Bleach to hearts content, and I do.

Also, water will last longer using bleach, then only Dichlor. Here in Chicago, I need it to last as long as possible during the winter.

Bottom Line: The only reason it seems more complicated is the initial step. However, the industry could make it much easier on us, if they sold little CYA/Borates packets to add to the tub first on refill. Then told us to use bleach. There would be no need for Dichlor period.

I feel kinda funny defending your own method to you.

[chem geek]

You don't need to convince me of the benefits of the method. If TinyBubbles and others who had issues were to come back and try again but this time not only with low TA (and yes, they tried lowering it to at least 70 ppm if I recall), but also to use Borates, then that would be great to know if that helps. TinyBubbles also reported more loss of chlorine using bleach than using Dichlor, though others did not report such differences.

Also, there was someone on this forum (I forget who [EDIT] I found the post and it is here from Shaamus [END-EDIT]) that reported different degradation rates for hot tub covers and it pretty much tracked the degree of strong oxidizer that was used such that the order from best (slowest degradation) to worst was: [EDIT] Biguanides; N2 + MPS dosing + Dichlor shock; ecoOne + Dichlor shock; Bromine activated by MPS; Frog + Dichlor or Bromine dosing + MPS shock; Dichlor dosing + MPS shocking; Bromine dosing through floater + MPS shocking. [END-EDIT] Presumably Dichlor-then-bleach would be worse than Dichlor-dosing and quite a bit better than bleach only (based on relative concentrations of active chlorine).

I guess I'm still very wary and sensitive after the chewing out so would personally prefer offering an alternative to try if it works for someone rather than say "this is THE way to go". Like anything else new, some issues were found initially and that have been mostly worked out or resolved. This is similar to the situation with pools where I think it's up to the pool owner to decide if the convenience of using Trichlor tabs/pucks along with weekly algaecide to prevent algae is better for them than having to add chlorinating liquid or bleach frequently.

Richard

[Nitro]

You don't need to convince me of the benefits of the method. If TinyBubbles and others who had issues were to come back and try again but this time not only with low TA (and yes, they tried lowering it to at least 70 ppm if I recall), but also to use Borates, then that would be great to know if that helps. TinyBubbles also reported more loss of chlorine using bleach than using Dichlor, though others did not report such differences.

Also, there was someone on this forum (I forget who) that reported different degradation rates for hot tub covers and it pretty much tracked the degree of strong oxidizer that was used such that natural enzymes were lowest, N2/MPS-only was next, N2/MPS with weekly Dichlor was next, N2/low-chlorine-Dichlor with weekly MPS was next, then Dichlor-only and the worst was bleach-only. Presumably Dichlor-then-bleach would be worse than Dichlor-only and quite a bit better than bleach only (based on relative concentrations of active chlorine).

I guess I'm still very wary and sensitive after the chewing out so would personally prefer offering an alternative to try if it works for someone rather than say "this is THE way to go". Like anything else new, some issues were found initially and that have been mostly worked out or resolved. This is similar to the situation with pools where I think it's up to the pool owner to decide if the convenience of using Trichlor tabs/pucks along with weekly algaecide to prevent algae is better for them than having to add chlorinating liquid or bleach frequently.

Richard

I just re-read that thread. I only saw TinyBubbles mention TA when he said it's between 60-80 with a test kit. There's a big difference between 60 and 80 when it comes to pH creep. I'd bet if he lowered TA to 50-60, he would have been fine. Not to mention adding Borates. Was there anyone else having pH creep issues other then TinyBubbles?

Regarding his Chlorine loss. I bet he had something in his tub using up the FC and causing the high demand. I know he had an ozonator, but I don't believe that was his only problem. My tub uses ~22% FC per day with no use. So if I shock to 12 ppm, the next day it will be 9.3, then 7.3, 5.5, 4.4, 3.4, 2.7, 2.1... I have confirmed this by testing. Which begs the next question. Has anyone else had problems with chlorine loss using bleach other than TinyBubbles?

As far as the chewing out. Watersentinel was not listening to facts, logic and common sense. He was only bent on making his point and nothing else. That's the reason he joined. And if you noticed, he has not been around since. We (on the other hand), are here to learn, and to try to help others.

I do agree the individual should weigh all the options before making a decision about sanitation. However, I'm finding the advantages of the Dichlor/Bleach method over the Dichlor Only method are far outweighing the disadvantages. In my case, and many others, ph Creep is not an issue. So if it comes down to a choice between D/B and D, I think the choice is clear. That's not to say Bromine or N2 shouldn't be considered. I'm just comparing B/D to D.

Maybe we should create little CYA/Borate packets to add to the tub at the start. That would simplify the process a great deal. We could take the Hot Tub Industry by storm.

[chem geek]

Many of the people who tried Dichlor/Bleach saw a pH rise at the point they switched to bleach, but initially they mostly had higher TA since they were changing methods from Dichlor-only which needed that higher TA for more stable pH otherwise some even saw a pH drop when using Dichlor-only. People would try lowering their TA and that helped, but many still saw a pH rise. They probably didn't lower the TA as low as 60 ppm in most cases (though I think that some may have), but the main factor was probably that Borates weren't being used since that certainly slows the rate of rise even if (in theory) it doesn't change the amount of acid needed.

I believe that Borates was something that waterbear talked about in this forum, especially after his validation of its usefulness in pools in The Great Tetraborate Experiment.

You make a very good point about an initial CYA and Borate addition kit since adding the CYA up front helps reduce over-chlorination in that first week or so until the CYA level gets higher. That's the currently biggest "chlorine too strong" problem with both Dichlor-only and Dichlor/Bleach. During those first few days, the chlorine concentration in the hot tub is too strong. If after a fresh refill one did a higher-than-normal dose of Dichlor, then that at least limits the timeframe for exposure to be shorter, though the FC would be higher. If one added CYA to the water first, then such overdosing issues go away and would be a help towards making hot tub covers last longer, regardless of method (i.e. Dichlor-only or Dichlor/Bleach). CYA is available in pure form in two ways. One is as a powder that is acidic, but it dissolves very slowly, at least at pool temps. I have no idea how much faster it dissolves in hot spa water. The other form is as a liquid (slurry) that is fairly pH neutral and dilutes quickly and is shown here: Natural Chemistry Instant Pool Water Conditioner. Unfortunately, these products are only sold for pools so their quantities are far larger than one would need for a spa.

I received a PM from someone who was using Spa Magic which is an enzyme product that also appears to have a strong pH buffer as well. They were adding about a cup or more of bleach every week or so to keep the water clear and their soft tub was small (about 220 gallons) so that was 17.5 ppm FC with no CYA. They found that they had to change the rings on their jets twice and that their liner felt rough. The deterioration of these rings is likely due to the exceptionally high levels of chlorine from the bleach and the roughness of the liner could have been scale since the pH with the enzymes is to be maintained between 8.0 and 8.4 and the TA was also high (though the CH was low). The point is that using pure bleach without any CYA in the water is very, very bad.

I'd like to compute some relative active chlorine concentrations with the different methods. Do people generally keep their spas heated at all times or are they put on timers for quick heating before you get in? If they vary in temperature between heating cycles, then how low does the temperature go assuming the spa is covered? The active chlorine concentration varies with temperature where 4 ppm FC at 20 ppm CYA at a pH of 7.5 this is 0.10 ppm at 77F but is 0.36 ppm at 104F. What this means is that at 77F, 20 ppm CYA cuts down the active chlorine concentration (which without CYA is about half the FC) by a factor of around 20, but at 104F it cuts it down by a factor of around 5.6 which is still significant, but not as dramatic as at lower temperatures. My initial recommendation of a 20 ppm CYA level was very conservative since it stemmed from the hot tub itch/rash/lung incidents, but it seems that it's probably OK to go up to about 50 ppm and still be safe. It's a spectrum of risk and there's no single defined point to pick, but I'd like to balance the harshness of the water on spas (especially covers) vs. the ability to kill the bacteria that causes hot tub itch. Maybe 50 ppm CYA would be OK; 20 ppm may be too conservative; 30 ppm CYA might be an OK compromise.

[Nitro]

Many of the people who tried Dichlor/Bleach saw a pH rise at the point they switched to bleach, but initially they mostly had higher TA since they were changing methods from Dichlor-only which needed that higher TA for more stable pH otherwise some even saw a pH drop when using Dichlor-only. People would try lowering their TA and that helped, but many still saw a pH rise. They probably didn't lower the TA as low as 60 ppm in most cases (though I think that some may have), but the main factor was probably that Borates weren't being used since that certainly slows the rate of rise even if (in theory) it doesn't change the amount of acid needed.

According to my expereince, a TA of 50-60 gives a pretty stable pH, even without Borates. That means rising pH using bleach is no more of a problem than falling pH is with Dichlor. Adding Borates locks pH solid. As I'm sure you've read, Laura has her pH pretty stable between 7.6.7.8. She hasn't added acid since we helped her, a week ago. It will be interesting to see how long she can go without adding acid, when her TA is 75.

I believe that Borates was something that waterbear talked about in this forum, especially after his validation of its usefulness in pools in The Great Tetraborate Experiment.

You make a very good point about an initial CYA and Borate addition kit since adding the CYA up front helps reduce over-chlorination in that first week or so until the CYA level gets higher. That's the currently biggest "chlorine too strong" problem with both Dichlor-only and Dichlor/Bleach. During those first few days, the chlorine concentration in the hot tub is too strong. If after a fresh refill one did a higher-than-normal dose of Dichlor, then that at least limits the timeframe for exposure to be shorter, though the FC would be higher. If one added CYA to the water first, then such overdosing issues go away and would be a help towards making hot tub covers last longer, regardless of method (i.e. Dichlor-only or Dichlor/Bleach). CYA is available in pure form in two ways. One is as a powder that is acidic, but it dissolves very slowly, at least at pool temps. I have no idea how much faster it dissolves in hot spa water. The other form is as a liquid (slurry) that is fairly pH neutral and dilutes quickly and is shown here: Natural Chemistry Instant Pool Water Conditioner. Unfortunately, these products are only sold for pools so their quantities are far larger than one would need for a spa.

On a fresh fill, I shock mine to FC 12 ppm, and then let the jets/air run for a couple hours before covering. Not ideal, but I'm hoping to cut down on cover damage. The ideal would be to have a little kit that adds the correct amount of CYA and Borates. Not only would it eliminate overchlorination issues, but it would simplify the process. I'm sold.

Until those packets are available, I may just buy that Liquid CYA for $20 a gal. I'm running low on Dichlor anyway. According to the directions, 3 oz will give you ~30 ppm in a 320 gal tub. That's ~40 water changes, or ~10 years. How long does this stuff last?

I received a PM from someone who was using Spa Magic which is an enzyme product that also appears to have a strong pH buffer as well. They were adding about a cup or more of bleach every week or so to keep the water clear and their soft tub was small (about 220 gallons) so that was 17.5 ppm FC with no CYA. They found that they had to change the rings on their jets twice and that their liner felt rough. The deterioration of these rings is likely due to the exceptionally high levels of chlorine from the bleach and the roughness of the liner could have been scale since the pH with the enzymes is to be maintained between 8.0 and 8.4 and the TA was also high (though the CH was low). The point is that using pure bleach without any CYA in the water is very, very bad.

Funny you should mention that, because I received a PM form the same person. I told them the same thing, that using bleach without CYA could be causing the damage.

I'd like to compute some relative active chlorine concentrations with the different methods. Do people generally keep their spas heated at all times or are they put on timers for quick heating before you get in? If they vary in temperature between heating cycles, then how low does the temperature go assuming the spa is covered? The active chlorine concentration varies with temperature where 4 ppm FC at 20 ppm CYA at a pH of 7.5 this is 0.10 ppm at 77F but is 0.36 ppm at 104F. What this means is that at 77F, 20 ppm CYA cuts down the active chlorine concentration (which without CYA is about half the FC) by a factor of around 20, but at 104F it cuts it down by a factor of around 5.6 which is still significant, but not as dramatic as at lower temperatures. My initial recommendation of a 20 ppm CYA level was very conservative since it stemmed from the hot tub itch/rash/lung incidents, but it seems that it's probably OK to go up to about 50 ppm and still be safe. It's a spectrum of risk and there's no single defined point to pick, but I'd like to balance the harshness of the water on spas vs. the ability to kill the bacteria that causes hot tub itch.

I keep mine at one temp, 98 in the summer, 100 (so far) in the winter. I can't speak for everyone, but I believe most people keep their spas at one temp. It takes my spa roughly 15-20mins to raise it one degree, with cover off and jets/air running. So it's not too practical to heat the tub up more than a degree or two before getting in.

[chem geek]

Until those packets are available, I may just buy that Liquid CYA for $20 a gal. I'm running low on Dichlor anyway. According to the directions, 3 oz will give you ~30 ppm in a 320 gal tub. That's ~40 water changes, or ~10 years. How long does this stuff last?

I don't know how long it will last, but I've had E-mail conversations with the inventor of that product so I'll ask him if he knows. It's an organic compound so it's not like plain inorganic salts, acids and bases that last for years and years. On the other hand, it may not be as unstable as organic dyes or FAS-DPD reagent.

Thanks for the info on tub temp. I'll assume a constant worst-case temp of 104F. I'll report back when I come up with some numbers. Happy Thanksgiving!

[Nitro]

I don't know how long it will last, but I've had E-mail conversations with the inventor of that product so I'll ask him if he knows. It's an organic compound so it's not like plain inorganic salts, acids and bases that last for years and years. On the other hand, it may not be as unstable as organic dyes or FAS-DPD reagent.

Well if you know the inventor, ask him if he can produce it in Pint or Quart size.

Thanks for the info on tub temp. I'll assume a constant worst-case temp of 104F. I'll report back when I come up with some numbers. Happy Thanksgiving!

No problem. Keep us updated. Happy Thanksgiving to you to.

[cashews]

Question. I used dichlor at the fresh fill, then switched to bleach. My CYA is about 30. My TA is around 80. From the chart in my Taylor kit, a range of 80-100 is best when using bleach. Is that correct? If that's right, then, isn't your recommendation of a TA of about 60 too low for the dichlor/bleach method?

I do experience a upward trend in my pH now and then, but have been dealing with it with pH down. I in turn need TA up now and then.

I just thought a TA of 50-60 is way too low according to my Taylor kit.

thanks for your thoughts!

[chem geek]

The 80-100 ppm for using a hypochlorite source of chlorine is what is normally given as normal for pools where aeration isn't as strong as it is in spas. A higher TA results in a faster pH rise from aeration so the only issue with a lower TA is with the saturation index and you can see from the Taylor wheel in your kit that at higher spa temperatures, this isn't as much of a problem and in any event can be compensated with higher Calcium Hardness (CH). You can also use The Pool Calculator to calculate the saturation index -- it gives results similar to the Taylor wheel.

If you don't add anything to increase the TA, then it should drop over time between the aeration and your acid addition and you should find that the rate of pH rise slows down as the TA drops. So just keep an eye on the TA to not let it get too low, but going below 80 is not a problem in a situation where the pH normally rises.

I wouldn't go below a TA of 50 and probably 60 or 70 will be good enough for you to reduce your pH rise. If the pH rise is still noticeable or an issue for you, then the use of borates (as described in Nitro's post on the dichlor/bleach method) can help reduce the frequency of your acid addition.

Richard

[cashews]

The 80-100 ppm for using a hypochlorite source of chlorine is what is normally given as normal for pools where aeration isn't as strong as it is in spas. A higher TA results in a faster pH rise from aeration so the only issue with a lower TA is with the saturation index and you can see from the Taylor wheel in your kit that at higher spa temperatures, this isn't as much of a problem and in any event can be compensated with higher Calcium Hardness (CH). You can also use The Pool Calculator to calculate the saturation index -- it gives results similar to the Taylor wheel.

If you don't add anything to increase the TA, then it should drop over time between the aeration and your acid addition and you should find that the rate of pH rise slows down as the TA drops. So just keep an eye on the TA to not let it get too low, but going below 80 is not a problem in a situation where the pH normally rises.

I wouldn't go below a TA of 50 and probably 60 or 70 will be good enough for you to reduce your pH rise. If the pH rise is still noticeable or an issue for you, then the use of borates (as described in Nitro's post on the dichlor/bleach method) can help reduce the frequency of your acid addition.

Richard

Will a 50-70 TA harm your heater or anything else on your spa? I swear I read a heater issue for low TA's.

BTW, thanks for the good explanation!

[Hillbilly Hot Tub]

I am not against bleach in the proper situation, but it has its disadvantages.

People tend to hear they can use bleach, so they just dump bleach in as stated, then issues arise. People also follow the directions on the rest of the chemicals, thus not having the proper Alk, knowing how much borates to add ect, and then they have problems.

It can get very confusing to the typical homeowner, they read on a forum to do this, then forget the exact amounts, so follow the directions on the test kit or bottle ect.

I feel you need to be well versed in water chemistry to be able to use the bleach method safely, many people are not and do not want to be. Each system has advantages and disadvantages to it, it whats best for each individual. People in the industry see what happens on hundreds of tubs, we have learned what most people are willing to do to maintain the tub, so we look at an overall picture.

Don't get me wrong, Richard and I have talked back and forth on the forum a bit and I do not knock his bleach therory, it just may not be for everyone, such as biguinades are not or bromine is not ect...ect... I just dont like statements such as this is the best, cheapest ect, it may not be for some people. I personally do not beleive there is a specific best system, it all depends on individuals.

[Nitro]

Will a 50-70 TA harm your heater or anything else on your spa? I swear I read a heater issue for low TA's.

As long as your water is balanced, your tub is safe. For instance, if your pH is 7.8, TA is 60 and CH is 200, your tub is well balanced. The problem comes when your TA is low AND your pH is low.

[cashews]

Will a 50-70 TA harm your heater or anything else on your spa? I swear I read a heater issue for low TA's.

As long as your water is balanced, your tub is safe. For instance, if your pH is 7.8, TA is 60 and CH is 200, your tub is well balanced. The problem comes when your TA is low AND your pH is low.

Gotcha. I'm one of those that is going to use the bleach method. I'm kind of a slave to the numbers right now, but I'm dedicated to getting it right. So since I'm willing to put in the effort, I think this method is for me. I want my investment to last!

Thanks guys.

[Nitro]

I am not against bleach in the proper situation, but it has its disadvantages.

People tend to hear they can use bleach, so they just dump bleach in as stated, then issues arise. People also follow the directions on the rest of the chemicals, thus not having the proper Alk, knowing how much borates to add ect, and then they have problems.

It can get very confusing to the typical homeowner, they read on a forum to do this, then forget the exact amounts, so follow the directions on the test kit or bottle ect.

I feel you need to be well versed in water chemistry to be able to use the bleach method safely, many people are not and do not want to be. Each system has advantages and disadvantages to it, it whats best for each individual. People in the industry see what happens on hundreds of tubs, we have learned what most people are willing to do to maintain the tub, so we look at an overall picture.

Don't get me wrong, Richard and I have talked back and forth on the forum a bit and I do not knock his bleach therory, it just may not be for everyone, such as biguinades are not or bromine is not ect...ect... I just dont like statements such as this is the best, cheapest ect, it may not be for some people. I personally do not beleive there is a specific best system, it all depends on individuals.

I agree there advantages and disadvantages to everything, including owning a hot tub. I also don't think bleach is the best method for everyone. If someone can't/won't check their tub everyday, especially for the first month or two, it's not for them. They should look into Bromine. However, I'm just comparing Dichlor/Bleach to Dichlor Only. Frankly, there is a correct way to use Chlorine, and an incorrect way to use it. Just because the Dichlor Only method is the "standard way", and appears to be easier, it's not the true correct way to use Chlorine. There is no logical reason to continually add CYA to your tub, period.

The only reason people make the mistake of pouring bleach into their tubs without CYA is because they're not educated. Who's job is it to educate them, their dealer. If dealers (and the industry) were to teach them the correct way to use bleach, I bet it would rarely happen. Not to mention they would have a lot less problems with their water. It's not difficult to learn the Dichlor/Bleach method. Quite frankly, if someone isn't capable of learning it, they won't be able to learn to keep their water maintained with any method.

People buying a hot tub should know there is a learning curve to maintaining the water, just like maintaining a car. I see a problem where a lot of dealers (not all) are selling tubs to people who if they knew all that it takes to maintain the water, they wouldn't have bought it. If dealers (and the industry in general) would just teach people the correct way to use the different methods, they might have less customers, but their customers would have a lot less problems with their water and they would be much happier.

Bottom line: Instead of teaching people an incorrect way to do something, just to make it easier, the Industry should be coming up with an easier way to do it correctly. Like manufacturing CYA packets to add to the tub at start up, then instruct them to use bleach. Why do you suppose they're not doing that? ($$$) After all, dealers (not all) sell their customers a bunch of stuff they don't need, then instruct them how to add it to their tubs. The problem is not that customers are not following dealer's (the industry's) directions. The problem is they are.