Suggestions for chlorine reading zero every day

[orellius]

Hello, 

Sorry long post not sure how to write this shorter. 

Looking for a bit of help. We bought a 1000L RotoSpa (Canadian one) in the summer. This is our 2nd fill. On this fill I tried to switch to the dichlor/bleach method because through suggestions of others, we were previously on the Beachcomber CareFree system on the first water fill, and our CYA of course went way up and eventually we drained the tub after just 2 months after fighting PH/Alk issues.

We are on an acreage and cannot use our well water, which is on the extreme level of stink from H2S. So we have potable town water trucked in, which is $200 a pop. So we want to make the water last 6 months if possible.

Yes I know and have read on these forums that Beachcomber **** is not recommended, that is why we are getting on the bleach method. It was recommended to us prior to me knowing of these forums. As you will see below I am still using some of their products because I have them, but am not using the Boost/dichlor stuff, and am willing to drop all the other **** too if needed. 

I am using a Lamotte ColorQ 2X system for testing, and some Lamotte test strips as a backup/reference.

For chlorine I am using Aquarius SHC pool chlorine (10.3%). It seems to take about 200ml of this to get it from 0 to 10 FC. I am hoping that seems about normal (1000L tub)?

Anyway, I am having a problem with chlorine demand, it keeps dropping to zero after I raise it up top 10. FYI, when I say zero in this post, it's more like 0.25-0.5 FC. pretty much zero. The water was fine for a few weeks after the fill. We got it filled on Halloween. I used my existing CareFree Boost to for the 1st week or so to get the CYA up to 30, which it is still at. Then I switched to the SHC. My initial chlorine demand tests were around 50%. Seems like it should have been much less with new water, but I didnt know better so I just went with it and kept monitoring the water daily, adding the chlorine as we needed it.

I was maintaining, without really any additives, PH of 7.6-7.8, TA was 80 a couple weeks ago, but is now around 100. CH = 160. I don't seem to have any issues keeping the water chemistry in line, far easier than it was with my first fill, but I understand my TA should be around 80, so I am working on getting that back down today.

Here's the kicker (I assume). I had continued to use the CareFree (not the boost, the 4-in-1). I already had 2 small bottles of it and thought it was ok to keep using with this new chlorine method. I was more after the only some parts of it (water balance/clarity, foam/scum prevention, etc). But it has MPS in it also, which I figured was harmless after doing some reading (perhaps I am wrong?). Since the tub fill, I've been adding the recommended weekly dose.

I've also been using weekly (as recommended on the bottle) Beachcomber Soft, which I understand is borate salts, and some apples...

Now the problem is over the last 1-2 weeks I found the chlorine would be zero, after bumping it up to 10 FC 24 hours prior. So I re-read the threads, and found to do 10 FC again, so I did, again it was zero. I did this I think 3-4 days and got the same result. So I followed the other advice, shock with MPS. I had just done the weekly 4-in-1 CareFree (which has MPS) on this past Saturday. It was Tuesday when I tried the "shock with MPS" option, and instead of CareFree, I used the 1000L recommended dose of this other stuff, Aquarius (Canadian Tire) non-chlorine spa shock, which I believe is basically the same as CareFree. That night I used SHC again and put it back to 10 FC, the next day it was zero, I added 10 FC again, and today it's zero. 

Now what? So frustrating, I thought I had this water figured, for a few weeks then it went to ****. I REALLY do not want to drain the water again due to the cost of the water truck, and the weather/cold. 

Any suggestions, besides ditch the Beachcomber crap? I don't want to just shock it again with MPS if it won't help. And I don't want to keep bumping it to 10 FC if that also isn't helping get the CD back in line. Do I need to go higher than 10 FC?

I was doing some further reading here and finding that MPS will throw off the FC readings. Does anyone know what this really means? Like it might read zero when it actually isn't? I get the same readings from the liquid re-agent test as I do the test strip. 

 

I really appreciate any help, thanks in advance. Sorry if some of this stuff is n00bish, I am new to it you know...lol. This water chemistry bugs the crap out of me because it seems to simple, and I have an engineering background, and it makes me feel stupid now. Haha. 

[RDspaguy]

Ok. First off, I have no clue what apples are doing for you.

If your spa has an ozone generator it is doing exactly what it should. Stay with the dichlor/bleach method, use less, and enjoy your (nearly) chlorine free soak. Add chlorine after each use. It's obviously ok if you overdo it, and you don't need to shock.

Ditch the mps. 

Use Ahhsome spa cleaner before your next water change.

[orellius]

25 minutes ago, RDspaguy said:

Ok. First off, I have no clue what apples are doing for you.

If your spa has an ozone generator it is doing exactly what it should. Stay with the dichlor/bleach method, use less, and enjoy your (nearly) chlorine free soak. Add chlorine after each use. It's obviously ok if you overdo it, and you don't need to shock.

Ditch the mps. 

Use Ahhsome spa cleaner before your next water change.

It just has an apple scent, I was just being silly. 

It does not have an ozone generator. 

Thanks for the response but I'm confused as to why I'm reading a lot of info here about trying to keep a chlorine residual (say 2.0), and that chlorine demand is important and should be 50% or lower. Mine is 100%, is it not? and that is bad, correct? But you are saying it's ok? I'm worried about it going to zero, and causing problems as the guides indicate it will. thanks for the input. 

[RDspaguy]

I'm saying it's ok if you have an ozone generator, as ozone burns off chlorine. That is not the same as chlorine demand. In a covered spa, you are the main (virtually only) source of contamination. If you add chlorine after you use the spa, about enough to establish a 2-3ppm per person (plus a little extra to be sure), you will sanitize the water. You close your cover, and soon have a 50% or higher cc (which would normally require a high ppm shock to eliminate) but nothing else is getting in there. Meanwhile, your ozone is burning off your cc, then your remaining fc down to .5ppm or so. Then, twenty-something hours later you open the cover to no cc and almost no fc, and no pathogens. That's what ozone is for, in my opinion. Oh sure, it is an impressive pathogen slayer, but it only treats the water in the pipe and returns it to a dirty tub. 

UV will have a similar effect.

Without ozone or UV, I would say you have biofilm in the pipes, and need to use that Ahhsome now. But you have to drain after you use it.

I know, it's brand new. Those are the worst. The last thing they do at the factory is wet test the spa. Then they pump out the water, leaving several gallons stuck inside the pipes, and put it in storage, onto a truck, in storage at a dealer, and eventually your back yard. I could tell you about some of the nasty crap I have seen come out of pipes on a new spa delivery, but I really don't like to think about it.

Search the terms "biofilm" and "ahhsome" on this forum for some interesting reading.

@waterbear, anything you'd like to add?

 

[orellius]

8 hours ago, RDspaguy said:

I'm saying it's ok if you have an ozone generator, as ozone burns off chlorine. That is not the same as chlorine demand. In a covered spa, you are the main (virtually only) source of contamination. If you add chlorine after you use the spa, about enough to establish a 2-3ppm per person (plus a little extra to be sure), you will sanitize the water. You close your cover, and soon have a 50% or higher cc (which would normally require a high ppm shock to eliminate) but nothing else is getting in there. Meanwhile, your ozone is burning off your cc, then your remaining fc down to .5ppm or so. Then, twenty-something hours later you open the cover to no cc and almost no fc, and no pathogens. That's what ozone is for, in my opinion. Oh sure, it is an impressive pathogen slayer, but it only treats the water in the pipe and returns it to a dirty tub. 

UV will have a similar effect.

Without ozone or UV, I would say you have biofilm in the pipes, and need to use that Ahhsome now. But you have to drain after you use it.

I know, it's brand new. Those are the worst. The last thing they do at the factory is wet test the spa. Then they pump out the water, leaving several gallons stuck inside the pipes, and put it in storage, onto a truck, in storage at a dealer, and eventually your back yard. I could tell you about some of the nasty crap I have seen come out of pipes on a new spa delivery, but I really don't like to think about it.

Search the terms "biofilm" and "ahhsome" on this forum for some interesting reading.

@waterbear, anything you'd like to add?

 

Any harm in using a floater with trichlor pucks for a couple months to keep a residual in the tub, letting the CYA increase obviously, but buying us some time before we do a water switch and clean the tub out? Seems like a bandaid fix, but we aren't getting sick, no rashes or itches, water seems clean. I actually already have a floater and pucks, was given to us by a family member. We used it a bit with our last water, but eventually took it out.

Man I really don't want to dump this water due to the whole water truck dilemma. What are the chances that I may have to do Ahh-some twice? I read that on their website it could be the case, depending. Meaning I use it, then drain it, the water truck guy comes, fills it, I use Ahh-some again right then with cold water, and I probably have to pay him to wait around while we deal with that and drain it again. The alternative is hope you don't need it twice, but if you do, I'm swapping the water again in a month. 

Man I wish I had clean tap water. Frickin country living. 

[RDspaguy]

The issue with tablets is low ph and the damage it causes, especially if the floater end up in or near the skimmer.

I would treat the same water twice. Once the gunk from the first use stops appearing on the shell and the foam goes down, add another dose if you are concerned. I used it once to remove the thick buildup in my thread on biofilm. I really can't imagine needing to do it more than once. Did you see my thread "Ever wonder what biofilm looks like?"? 

[waterbear]

STOP!!!!!! It's testing error!!!!!!!!!

You are using LaMotte test kits. They use the DPD testing method and their particular reagent WILL bleach out at FC levels above abou 5 ppm. You have also used MPS which can interfere with testing for chlorine.

My advice is bit the bullet and spend the money on a Taylor K-2006 which uses the FSD-DPD testing method and is acurrate and precise (not the same thing) at much higher sanitizer levels (up to around 20 ppm) by adding additional DPD powder until the pink color develops and doesn't bleach out. If you have MPS in the water you will also need the Taylor K-2041 MPS interference remover add on for the K-2006/K-2005. Even Taylor's DPD test kit (K-2005) will work up to 10 ppm FC and has instructions for diluting your sample if it's bleaching out but the small amount of money you save by buying the K-2005 is not worth it since the FAS-DPD testing method is MUCH easier since you are not trying to match up shades of red but are using a titration (drop count) test with a color change from pink to colorless that even colorblind people can use.

To verify that your chlorine is actually very high get a cheap OTO test kit (Taylor has the K-1000 but you should be able to fine a cheap 2 way or 3 way test kit with OTO just about anywhere , including Walmart, Home Depot, Lowes, etc.) You can tell it's an OTO test because the comparator for chlorine/bromine will have color block with different shades of yellow instead of the red color blocks on a DPD test. I am pretty sure you will find that your sanitizer level (including any MPS in the water) will give you a reading that is off the scale. OTO tests total chlorine and MPS and will not bleach out.

 

[waterbear]

Don't use Trichlor, it will also raise your CYA levels but not as fast as Dichlor will. Also the very low pH will require a much higher TA to avoid pH crashes, particularly in the small amount of water found in a tub. A swimming pool has much more water and therefore is a bit more forgiving but trichlor and dichlor will eventually overstabilize a pool and require a series of partial drains and refills to get it back in line.

[orellius]

8 hours ago, waterbear said:

STOP!!!!!! It's testing error!!!!!!!!!

You are using LaMotte test kits. They use the DPD testing method and their particular reagent WILL bleach out at FC levels above abou 5 ppm. You have also used MPS which can interfere with testing for chlorine.

My advice is bit the bullet and spend the money on a Taylor K-2006 which uses the FSD-DPD testing method and is acurrate and precise (not the same thing) at much higher sanitizer levels (up to around 20 ppm) by adding additional DPD powder until the pink color develops and doesn't bleach out. If you have MPS in the water you will also need the Taylor K-2041 MPS interference remover add on for the K-2006/K-2005. Even Taylor's DPD test kit (K-2005) will work up to 10 ppm FC and has instructions for diluting your sample if it's bleaching out but the small amount of money you save by buying the K-2005 is not worth it since the FAS-DPD testing method is MUCH easier since you are not trying to match up shades of red but are using a titration (drop count) test with a color change from pink to colorless that even colorblind people can use.

To verify that your chlorine is actually very high get a cheap OTO test kit (Taylor has the K-1000 but you should be able to fine a cheap 2 way or 3 way test kit with OTO just about anywhere , including Walmart, Home Depot, Lowes, etc.) You can tell it's an OTO test because the comparator for chlorine/bromine will have color block with different shades of yellow instead of the red color blocks on a DPD test. I am pretty sure you will find that your sanitizer level (including any MPS in the water) will give you a reading that is off the scale. OTO tests total chlorine and MPS and will not bleach out.

 

So you think the test water sample being clear (which it is when I say it reads zero), is only clear because of the method they use for testing, and the FC may actually be higher? Does this hold true for the Lamotte strips as well? They both read the same thing. What I noticed is if I test immediately, it is zero (0.25-0.5), but if I wait like 30 seconds it starts to turn pink. I could "blank" the test again with a clean sample, then test the same sample that is now pink, and it reads higher chlorine. The test kit says test immediately, so that's what I do. 

I actually had read somewhere months ago something relating to what you are describing, and Lamottte offers a "MPS-OUT" tab specifically for this, but I am unsure if this works with my specific test kit, and it was literally impossible to find online in Canada, and US dealers I could find didn't ship to Canada. Not sure why I didnt pin that as the issue now because I recall reading about it, but **** I hope I can sell this kit to someone locally, or my wife is going to **** on me. lol

I realize you don't know my water, but you are basically suggesting it may not be a biofilm issue? If I can get away with using this water for a couple months, that money buys me a new test kit. Then I can Ahh-some the water and drain it in the early spring as intended. 

Edit: forgot to mention, the test kit since I got it, and I believe in the manual, says it's good for 10 FC. And anything I test below 10 FC reads normally (so it seems), anything above 10 always reads like (13+, 12+, etc, with a frown face icon), so it clearly can't read above 10FC. Is it perhaps a different model you are thinking of that is limited to 5FC? And if I ditch the MPS completely, in say a week will it start reading normally and I can keep my kit? I just ordered some new re-agents as I was running low, another potential waste of money. Bah!

[orellius]

and I just did a test right now, I got 0.25. Blanked it, tested again, 0.5, then again 0.8. I waited a few minutes and it went dark red and tested at 13+

[waterbear]

Sigh. I know they said 10 ppm but I have used LaMotte an Taylor testing side by side an Taylor's is just better! Also, as far as the ColorQ goes you are  using what is basically a $100 colorimeter. When you consider that the Lamotte Waterlink Spin disk and the Hach colorimeter for pool water testing cost well over $1000 and closer to $2000 dollars and the only meters that Taylor offers are MyronL conductivity meters for TDS and salt it sort of puts the ColorQ into perspective. I know LaMotte claims 10 ppm but it is a colormetric test and what they don't tell you is that it can read low with high FC/MPS levels because of a partial bleach out (found out this little gem when I used to use the LaMotter waterlink system from their tech support) It has nothing to do with the model of meter, it's the reagents and the limits of colormetric testing. However, I can't put a lot of faith in a $100 colorimeter like the ColorQ either. You get what you pay for.

Taylor uses titrations  for most of their tests which do not have the same  limitation. Colormetric tests for santizer, TA, and CH or TH (total hardness, calcium and magnesium and a useless test for pools since CH is the parameter you need to calculate if your water is aggressive to plaster or not)i n most cases unless liquid reagents are used which leave out Professional Lamotte testing with the spin disk and the ColorQ kits with tablets instead of liquid reagents an ALL test strips. These can only test Total hardness.Once again, a limitation of colormetric test chemistry for these parameters.

Taylor kits are available in Cananda but at an inflated price which is set by the Canadian distributor. Even so they are still worth the money, especially when you put it into the perspective of how much the kit is compared to the price of your spa. A good test kit is probably the most important spa accessory you can buy. AS far as strips go, most are useless. The only ones I use are the LaMotte Borate strips (MUCH easier to read than Hach and Taylor's, which are identical to the Hach strips) and sometime I use the Hach/Aquachek salt titirator strips since they are less messy that Taylor's dichromate/silver nitrate titration test for NaCL.

One thing to consider, I actually understand the chemistry involved in what we are talking about and do have a background in chemistry (my first underdgrad major) and have been testing water for many many years (close to 50), not just for pool/spa use but also because of my hobby of tropical and reef aquaria. Many of the tests are identical, btw. I also have no affiliation with any pool or water testing company and have used just about every product for water testing out there over the years.

[waterbear]

20 minutes ago, orellius said:

and I just did a test right now, I got 0.25. Blanked it, tested again, 0.5, then again 0.8. I waited a few minutes and it went dark red and tested at 13+

I rest my case.

[RDspaguy]

You need some rest after all of that typing. 😉

But the biofilm advice still stands, and you should use Ahhsome at your next water change.

I also have no affiliation with any...😁

[orellius]

3 hours ago, waterbear said:

Sigh. I know they said 10 ppm but I have used LaMotte an Taylor testing side by side an Taylor's is just better! Also, as far as the ColorQ goes you are  using what is basically a $100 colorimeter. When you consider that the Lamotte Waterlink Spin disk and the Hach colorimeter for pool water testing cost well over $1000 and closer to $2000 dollars and the only meters that Taylor offers are MyronL conductivity meters for TDS and salt it sort of puts the ColorQ into perspective. I know LaMotte claims 10 ppm but it is a colormetric test and what they don't tell you is that it can read low with high FC/MPS levels because of a partial bleach out (found out this little gem when I used to use the LaMotter waterlink system from their tech support) It has nothing to do with the model of meter, it's the reagents and the limits of colormetric testing. However, I can't put a lot of faith in a $100 colorimeter like the ColorQ either. You get what you pay for.

Taylor uses titrations  for most of their tests which do not have the same  limitation. Colormetric tests for santizer, TA, and CH or TH (total hardness, calcium and magnesium and a useless test for pools since CH is the parameter you need to calculate if your water is aggressive to plaster or not)i n most cases unless liquid reagents are used which leave out Professional Lamotte testing with the spin disk and the ColorQ kits with tablets instead of liquid reagents an ALL test strips. These can only test Total hardness.Once again, a limitation of colormetric test chemistry for these parameters.

Taylor kits are available in Cananda but at an inflated price which is set by the Canadian distributor. Even so they are still worth the money, especially when you put it into the perspective of how much the kit is compared to the price of your spa. A good test kit is probably the most important spa accessory you can buy. AS far as strips go, most are useless. The only ones I use are the LaMotte Borate strips (MUCH easier to read than Hach and Taylor's, which are identical to the Hach strips) and sometime I use the Hach/Aquachek salt titirator strips since they are less messy that Taylor's dichromate/silver nitrate titration test for NaCL.

One thing to consider, I actually understand the chemistry involved in what we are talking about and do have a background in chemistry (my first underdgrad major) and have been testing water for many many years (close to 50), not just for pool/spa use but also because of my hobby of tropical and reef aquaria. Many of the tests are identical, btw. I also have no affiliation with any pool or water testing company and have used just about every product for water testing out there over the years.

sorry if there is a misunderstanding (to prompt the sigh), but I am not questioning or doubting anything you are saying as invalid. I am merely asking questions, trying to save my investment into this ColorQ tester and reagents. I fully appreciate the input and will likely be purchasing a Taylor kit as well. 

For the record, and this is just for fun, but I bought the ColorQ 2X Pro 7 model and it cost me $283 CAD all in!  I can get the K-2006 on Amazon for $180. Not that it matters, but at the time I didn't know there would be issues with certain tests (how could I really know, I was so new to water testing). I know I looked at them both at the time, and somehow ended up with the LaMotte. I'm sure pricing and such is different per dealer and country, but it definitely was not the cheap $100 version, if I compare it to the one you are saying I need and the price I can get them both for. I also realize you are likely talking about the quality of the sensor, not the actual unit/model. Either way, the Taylor is definitely cheaper where I would go get it. Granted, it may not be the same quality, as suggested. 

Anyway I havent convinced the wife to let me call the water truck and drain the water yet, I may order the kit and confirm the difference in readings (again, not that I doubt it, I just want to see it). Knowing myself I'll probably keep both kits for several weeks and run 2 tests at a time. I'll also get some Ahh-Some so I have it and wait for a good time to swap the water. 

[RDspaguy]

Listen to @waterbear. Nobody on this forum (or on earth, I believe) knows more about water chemistry. 

And I am pretty sure the sigh was from the fact that he just answered basically the same question in another thread. Poor waterbear repeats himself ALOT. 😉

[waterbear]

ColorQ meter is much less than the total price of the kit which also includes the reagents. In the  US your kit sell for about $100 less than you paid and I have seen it discounted on some sites for about $150 less. Taylor K-2006 can be had in the US for under $70. Prices are set in Canada by the Canadian distributors and are much higher for some reason (Import tax? Shipping? Currency Conversion? Greed?).

Lowry & Associates is the only Canadian distributor for Taylor and I'm not sure who the LaMotte distributor is at this time.

[orellius]

So after all this I am seriously thinking on switching to bromine. With all I am reading on the apparent ease of maintenance. I'm still reading on that topic and havent made a decision but I believe it's an easy switch and doesn't require new water, and more forgiving on the Ph, less often adding stuff like chlorine. 

I believe with so far what I'm reading that you'd still use MPS, but that wouldnt affect the tests (??), and my Lamotte machine will test for bromine, so I can keep my test kit. I REALLY did not like what I saw in the videos I watched on the Taylor kit on YouTube, the test method is a bit much, I could see myself constantly replacing reagents with the amount of drops I see them using, lol. That's not a knock on the system at all, it's to each his own for sure. I'm just hoping to keep mine. 

I really need this water to be EASY as I travel a lot and I need it easy for the wife when I'm gone.

I'm guessing then I'll have to deal with more TDS

[orellius]

@waterbear @RDspaguy

Hey Again, 

Hoping I can get some more of advice from you two, hopefully regardless of if you hate products like these? 🙂 Based on what I wrote above, being that I travel a lot and I need the water the be as maintenance free as I can get, for the wife, within reason (weekly, weekend maintenance is what I'd hope for, not daily)...

I realize you both are likely very against this stuff, but my wife has more family in her ear that are talking about Beachcomber stuff again. So we are considering this, or something similar from Canadian Tire for ease of access where we live. 

Just trying to educate myself and not buy something I don't need or can't use. And to hopefully keep using my ColorQ test kit without MPS interference. But I am fearing that bromine testing is interfered the same way (the test kit uses the same 2 DPD reagents for the bromine test, you just press the button on BR instead of TC...)

Again it's not me wanting these, just someone telling us to look into them. I can be persuaded into something else, I just need it to be easier maintenance during Monday to Friday when I travel. I'm liking stuff I read online about the pros/cons between bromine and chlorine systems.

1. Beachcomber Bromo Discs and/or Bromo Blast (or similar other brand product)

• using this, or some similar/local Canadian Tire bromine discs or granules, do you know if using these, along with non-chlorine shock, I'd still have the exact same DPD test interference? 
• The Bromo Blast label says 52.7% Sodium Dichloro-S-Triazinetrione, so this has the same stabilizer found in chlorine granules, so I still have to worry about CYA? Except that their Care Free Boost has 100% sodium dichlor, not 52%. Not sure if I am thinking about this correct. 
• The Bromo Discs label does not, so then that is different product and my concerns would then be TDS due to constantly dissolving tablets?
• They basically say it's one or the other, or even a combination of both. 
• If I have to drain the water every 3-4 months due to TDS, then I guess that is what I have to do, to make the water easier to maintain

2. Beachcomber Ultra (2-part) - Ultra Start, Ultra Shock (or similar)

• Would this be considered a "salt water" system? https://www.beachcomber.ab.ca/salt-systems - I'm asking because the tub manual does not recommend salt water systems, so then I can discount this product completely
• They also use "ultra shock" - which is MPS I believe
• Really hard to find any good info on these products - not sure if this is a "full salt water system" type thing, or if it's just "salty" and not quite, so is safe to use - not surer how else to explain my question, lol
• I guess I can't tell the difference, they both (discs/blast, and Ultra) say they are bromine systems. I'm just concerned with the MPS interference with bromine readings, and the fact that my tub says don't use salt water

 

[orellius]

if it helps, I should add that it's only 2 of us. Nobody else will ever be in the tub, we use it 3-4 times a week, 15-30 min. No parties, no high bather load. I guess I an hoping the TDS would climb slower due to this.

[RDspaguy]

Well, I am flattered to be listed alongside @waterbearin a chemistry thread, as he has forgotten more about it than I will ever know.😁

Bromine is old school, and a tried and true system. Not my favorite, true, but fine nonetheless.

100% dichlor is still almost half cya. The stuff listing 52% is probably part mps or something. Waterbear probably knows more on that.

[orellius]

14 minutes ago, RDspaguy said:

Well, I am flattered to be listed alongside @waterbearin a chemistry thread, as he has forgotten more about it than I will ever know.😁

Bromine is old school, and a tried and true system. Not my favorite, true, but fine nonetheless.

100% dichlor is still almost half cya. The stuff listing 52% is probably part mps or something. Waterbear probably knows more on that.

I mentioned you because you started helping me first and have been helpful so far! And you have a lot of posts, so you must know something. ha

[RDspaguy]

Just now, orellius said:

must know something.

Well, that depends on who you ask...😉

[waterbear]

You can use sodim hypochlorite (Liquid laundry beach) or other forms of chlorine to shock a bromine system and activate the bromine. Bleach is you least expensive option and is just as effective as any other form of chlorine for activating bromine. You DON"'T need MPS at all unless you want to use up the MPS you already have. It is expensive and causes sulfates to build up in the water, as does dry acid. This can necessitate more frequent water changes. TDS is a useless parameter that became popular in swimming poo water testing before the effects of high CYA level on chlorine were fully understood. The ineffectiveness of chlorine in the presence of high CYA was attributed to high TDS while in reality it had nothing to do with TDS at all!

AS far as DPD bleachng out and reading low when it's actually high, this will happen with bromine also. It is a limitation of DPD testing. Once again I suggest using Taylor FAS-DPD testing since it does not have this limitation. MPS will interfere with DPD testing or FAS-DPD testing if you use it. Period. Whether you use bromine or chlorine is immaterial. FWIW, Taylor DPD testing has similar limitations BUT they provide detailed instructions for diluting your sample to get a reading at higher sanitizer levels and also have the add on for removal of MPS interference. The FAS-DPD testing is much more immune to high sanitizer levels but if you are using MPS you still need the add on for MPS interference.

The reason you have to drain the water in a tu

b every 3-4 months has nothing to do with TDS. It has to do with buildup of oxidation by products such as sulfates from MPS and dry acid, Bromate or Chlorite and Chlorate in the water and the fact that a tub is normally covered and not exposed to UV from sunlight which breaks down some of the oxidation byproducts and since a pool is not covered the volatile oxidation byproducts can gas off. These also build up much faster in a tub because of the small water to bather load ratio compared to even a very small pool! You stated that you have a 1000 L spa (approx 264 US gallons) and that is VERY small. You also stated that there are 2 bathers and that is a very large load for such a small spa. Pools that are covered or indoors can also have the same problems and the use of UV, Ozone, and MPS in these cases can be helpful. Indoor pools also need good air handlers to keep the volatile byproducts from collecting in the air. 

2 part bromine is NOT a salt system. Salt system use electrolysis to convert salt into chlorine and require adding salt (sodium chlorine) to the water. The sanitizer is create in a salt cell that is powered by electricity. Chlorine gas is formed at the anode and hydrogen gas is formed at the cathode. The chlorine gas dissolves in the water forming sodium hypochlorite and the hydrogen gases off. A similar system can be used to form bromine sanitizer but it has been outlawed in Canada based on studies done on drinking water and not spas and pools. 

There are two ways to do bromine, 2 part and 3 part. 2 part bromine involves creating a bromine reserve in the water with sodium bromide an then oxidizing with either a chlorine source (such as the dichlor in the bromo blast) or MPS. Either one works but I prefer chlorine, particularly sodium hypochlorite, aka liquid pool chlorine or plain, unscented liquid chlorine laundry bleach without any thickeners or other additives because it is the most economical. Your bromoblast is a 2 part system where they combine the sodium bromide and oxidizer into one bag.

3 part bromine is the same as 2 part with the addition of adding a floater with bromine tabs. Bromine tabs contain an organic form of bromine AND chlorine  to provide the bromide ions and oxidizer, typically 1-bromo-3-chloro-5,5-dimethylhydantoin. However, tabs by themselves are going to be a chlorine sanitizer until a bromide reserve has built up on the water unless you start with a 2 part system and then add the floater. The advantage of a 3 part system is that, once you have a bromide reserve and have adjusted the floater correctly the system becomes self sustaining in maintaining the bromine levels in the tub. I used 32 step bromine for years when I had a stand alone hot tub. (My current house has a pool/spa combo that is using a chlorine salt system.) The only thing you need to do with a 3 step system is to shock it weekly to biweekly, depending on use, to bring your bromine levels above 10 ppm and let it drop while the spa is uncovered and circulating.

Beachcomber does have a liquid sodium bromine called Ultra Start. This will create your bromine bank. They sell their MPS to activate it but you can also you any chlorine source instead such as dichlor or bleach. This is a tru 2 part system since once you have your bromine reserve you don't normally need to add more every time, especialy if you add the floater with bromine tabs.

NO matter what system you use, bromine, chlorine, or biguanide/peroxidie (NOT recommended) you still need to do water changes every 3-4 months because of the water to bather load ratio and a 2 bather load in 1000L is HIGH!

 

[waterbear]

12 hours ago, orellius said:

I REALLY did not like what I saw in the videos I watched on the Taylor kit on YouTube, the test method is a bit much, I could see myself constantly replacing reagents with the amount of drops I see them using, lol. That's not a knock on the system at all, it's to each his own for sure. I'm just hoping to keep mine. 

You mean these videos? https://www.taylortechnologies.com/en/page/231/k-2006-complete-kit-with-fas-dpd

I gave you my advice on testing, follow it or not but I have a lot more experience in water testing than you do, If you are concerned abou the number of drops used in testing use a 10 ml sample instead of 25 ml. In fact, for the sanitizer test you want to use a 10 ml sample and if you calcium hardness is higher than bout 300 ppm you also can use a 10 ml sample. You only have an accuracy of 25 ppm instead of 10 ppm for the CH test and the chorine test .5 ppm instead of .2 ppm but you really don't need an accuracy of more than .5 ppm for FC or CC.

If you switch to bromine the kit is K-2106 for bromine. I am not a fan of the ColorQ nor the colormetric chemistry that LaMotte uses with their meter systems, including the professional ones that I have used in the past. Interestingly enough LaMotte used to make drop based kits very similar to Taylor's for pool professionals to use in the field but they tended to cost about twice as much as the equivalent Taylor kits, at least here in the US. IT seems they discontinued them in favor of the ColorQ, which probably simplifies the inventory of reagents they need to maintain and , I suspect, the profit margin on the meter itself.

[orellius]

4 minutes ago, waterbear said:

You mean these videos? https://www.taylortechnologies.com/en/page/231/k-2006-complete-kit-with-fas-dpd

I gave you my advice on testing, follow it or not but I have a lot more experience in water testing than you do, If you are concerned abou the number of drops used in testing use a 10 ml sample instead of 25 ml. In fact, for the sanitizer test you want to use a 10 ml sample and if you calcium hardness is higher than bout 300 ppm you also can use a 10 ml sample. You only have an accuracy of 25 ppm instead of 10 ppm for the CH test and the chorine test .5 ppm instead of .2 ppm but you really don't need an accuracy of more than .5 ppm for FC or CC.

If you switch to bromine the kit is K-2106 for bromine. I am not a fan of the ColorQ nor the colormetric chemisty that LaMotte uses with their meter systems, including the professional ones that I have used in the past. Interestingly enough LaMotte does make drop based kits very similar to Tayulor's for pool professionals to use in the field but they tend to cost (much) more than the equivalent Taylor kits, at least here in the US.

In your other post you said "swimming poo water". Jut having fun.  

May not have been those specific videos, was just searching on YouTube. It was more like some people by their pools showing how to use it. 

Ok so I can ditch MPS and therefore remove the issue of MPS interference. I wasn't suggesting I'd want to keep using it for any reason, I guess I hoped it wasn't going to affect the DPD test the same way with bromine, but now I have that answer! I'll still look into your kit suggestion, I just can't buy it right now with Christmas and I just bought a Starlink satellite dish last week! May finally have decent rural internet! The problem I am having is locating a source. I can find the kits, but not the refills very easily, and not that specific reagent mentioned earlier for dealing with the MPS issue, so I was scouring the Canadian interwebs for a while the other night and was feeling like I'd be in the same situation I am now, where reagents are hard to come by. It was a major struggle to get the re-agent refills for the LaMotte kit, and it seems to be similar with the Taylors, at least in Canada, so I'll keep digging. Sorry not meaning to argue on the kit suggestion, appreciate the advice it just seems like a struggle here to get these things. Like Canada is a 3rd world country or something. 

Back to the water, I already have 2 gallons of that Aquarius 10% SHC pool chlorine I can use. I have no issue with disposing of my MPS, I don't have much left. I just didnt want to buy a Beachcomber bromine system if it had MPS and that was still a not-recommended thing, which you confirmed. IF I went to a 3-part system, so I had the ease of the floater and pucks, then I'd be using a small amount of the SHC to shock, instead of MPS, this would be a weekly thing? Or a daily thing? Sorry if it's just a bit confusing, trying to get around MPS and now that pool chlorine is back in the mix instead, just a tad confusing. If I can get this system down where I can leave for 5 days during the week, and come back and shock it on Saturday, add some SHC to shock, that would be ideal. I mean it's not a deal-breaker for the wife to have to add a specific amount of chlorine during the week if required, but I can't have her doing digital or complex testing when I'm gone, she said she wants nothing to do with that.