Introduction With Insight Requested

[mlp00]

Edit: Oh, duh! After posting and seeing my post title, it dawned on me what my other question was! I'll save that for another post. I've asked the mods to change the title of this thread. In short, I believe the Ozone system in my tub is disconnected. Perhaps that will have an effect on the post below?

Thank you for this forum! I've already learned so much. I have a Taylor K-2006 and a bag of boric acid due for delivery Monday (working toward dichlor-bleach, eventually).

I'm 3rd owner of a 2008 Arctic Spas Frontier Legend without much insight as to its care before me. I've had it running for ~3 weeks. It's taken an extensive amount of mental/physical labor but it is now up and running great (electrical, leaks, heating, etc).

We had an itch developing but, I believe, it was attributed to letting the FCl slip over the holiday weekend - during which we used it excessively - and having a TA reading of 170. There were often times I would get blank FCl readings on strips. I've been tending to it laboriously over the last couple of days and I think I have it corrected. Based on the test strips, I would say TA is ~80 and pH is 7.2. I'm trying to bring the pH up by aerating at the moment. I've cycled through at least four 20 minute aeration sessions with only slight change. Is it safe to use pH up at this point?

I have a couple of other questions. First, if, come Monday, my CYA levels are appropriate (20-30 ppm) is there anything preventing me from dropping TA closer to 50, adding 50ppm borates, and moving to Bleach? I suspect the levels of CYA are not going to be ideal considering I've used nothing but CL / MPS over the last 3 weeks.

Next, the owners prior provided a SunPurity mineral cartridge which is currently in the filter basket. There isn't much left inside of it. I purchased a new one which actually contains contents! Should I install it? If so, I need some clarity as to how I maintain the tub: do I add MPS before and/or after use (they said 0.5 oz per person) and then check FCl, or vice versa, or just one or the other? I've been told, if properly monitored, CL is only necessary ~1-2 times / week. Confused...?

There was one other question but I can't recall what it was. Any help would be greatly appreciated.

Thanks again for all of the great knowledge

Edited January 9, 2016 by mlp00

[chem geek]

If you've never purged your spa, then on your next water change you should use Ahh-Some.

There is nothing about your water that would prevent you from lowering the TA and adding the Borates. You could use more Dichlor to buildup the CYA to 30-40 if you think it's on the low side now. After you switch to using bleach, you'd still use Dichlor about one day per month to keep the CYA constant since chlorine slowly oxidizes it.

So you'll need to decide which way you want to go -- with the Dichlor-then-bleach method or with the SunPurity mineral cartridge that uses silver ions so could be used with MPS (similar to Nature²) for a mostly chlorine-free experience. Usually to keep the water clear you'll still need to use some chlorine once a week or two. If you go with the silver ions with MPS you won't need your TA to be so low since MPS is net acidic and you'll periodically need to add baking soda (or pH Up) to keep the TA from falling.

If you are going to use MPS then you need either MPS test strips or if you use the Taylor FAS-DPD chlorine test then you need the Taylor K-2042 MPS interference remover so you will be able to distinguish between MPS and FC. Or you just measure total chlorine (FC+CC) and assume it's MPS.

As for how often you need to test and dose, you need to add oxidizer (MPS or chlorine depending on your method) after every soak, but whether you need to add more in between soaks depends on your chlorine demand between soaks. If the ozonator is disconnected, then your chlorine demand should be < 25% FC loss per day between soaks (not counting the 24 hours after a soak where obviously the demand is high from the bather load from the soak). If using MPS, then it should not drop as quickly.

[mlp00]

I haven't purged. I'll definitely do that next change (likely March when the temp picks back up).

I would prefer to go with Chlorine.

So, it's either SunPurity + MPS, or Dichlor-then-bleach? Ive been adding 0.5 oz Brilliance Oxidizer per person after each soak. With the current SunPurity cartridge being far expired and likely serving no purpose, is this unnecessary or even ill-advised? Should I return the new cartridge I bought?

As for my Ozone system: here are some pics

http://i.imgur.com/9tRuSgW.jpg

http://i.imgur.com/RLRsi6H.jpg

http://i.imgur.com/AwSiJBA.jpg

I'm very unfamiliar with these systems so I am only able to assume that the black cylindrical object in the 3rd pic is associated. It's so entrenched with spray foam that I can't really tell where it goes or what tubes are connected to it. It appears that it connects to an air control valve like this: http://i.imgur.com/cc824Qm.jpgbut in the corner of the tub.

What I can tell is that the black box in pic 1 is certainly plugged into the spa pak but there are no lights etc to indicate it is doing anything. In pic 2 you can see the tube on the floor that is folded over and crimped shut with a hose clamp. This seems somewhat concerning to me but it isn't leaking any water. If I follow it back it goes up into some more spray foam so I'm unsure of its purpose.

I do have a stream of bubbles coming from a vent near the bottom of my tub when the jets are on. Is this from the ozone system? What do I need to check to verify the system is doing anything?

[mlp00]

I haven't purged. I'll definitely do that next change (likely March when the temp picks back up).

I would prefer to go with Chlorine.

So, it's either SunPurity + MPS, or Dichlor-then-bleach? Ive been adding 0.5 oz Brilliance Oxidizer per person after each soak. With the current SunPurity cartridge being far expired and likely serving no purpose, is this unnecessary or even ill-advised? Should I return the new cartridge I bought?

As for my Ozone system: here are some pics

http://i.imgur.com/9tRuSgW.jpg

http://i.imgur.com/RLRsi6H.jpg

http://i.imgur.com/AwSiJBA.jpg

I'm very unfamiliar with these systems so I am only able to assume that the black cylindrical object in the 3rd pic is associated. It's so entrenched with spray foam that I can't really tell where it goes or what tubes are connected to it. It appears that it connects to an air control valve like this: http://i.imgur.com/cc824Qm.jpgbut in the corner of the tub.

What I can tell is that the black box in pic 1 is certainly plugged into the spa pak but there are no lights etc to indicate it is doing anything. In pic 2 you can see the tube on the floor that is folded over and crimped shut with a hose clamp. This seems somewhat concerning to me but it isn't leaking any water. If I follow it back it goes up into some more spray foam so I'm unsure of its purpose.

I do have a stream of bubbles coming from a vent near the bottom of my tub when the jets are on. Is this from the ozone system? What do I need to check to verify the system is doing anything?

After reading through some more posts of yours I see you've answered these questions ad nauseam So thank you for that! I see now I do not need MPS or SunPurity.

I just got email notification that my K-2006 was delivered! I am excited to get some accurate numbers tonight and will be stopping by the store to pickup some Bleach on the way home. The boric acid should be arriving soon as well.

So, I guess my remaining question at this time is how to tell if the Ozone system is hooked up. I'll try to do some more digging in the meantime.

Thanks again

[mlp00]

Initial water test results:

FC 4.8

CC 0.8

pH 7.8

TA 80

CYA 72

CH 130

SI 0.1

Post-soak FC was 1.8 ppm after ~2.5 bather hours tonite. I added 8.33 tsp of Dichlor for my 334 gallon tub.

What are my options for reducing CYA to get it back to 30 ppm to facilitate the switch to Bleach? Is water replacement my only option? According to the calculator, I would have to replace 58% (!) of the water. While unfortunate, I don't mind doing the replacement once my boric acid arrives.

[chem geek]

You can only reduce CYA by water dilution. I'd just live with it since it isn't terrible and will slowly get oxidized by chlorine at the rate of around 5 ppm per month (maybe somewhat higher at your current CYA level). Up to you though -- you can go down just to 40 ppm if you like.

If you won't be soaking every day, then carefully measure your 24-hour FC loss rate. If it's high like 50% or more, then you probably have a functioning ozonator while if it's low at less than 25% then your ozonator may not be working.

You'll want to get your TA lower closer to 50 ppm before you add the boric acid (perhaps to 60 since the boric acid will be slightly acidic).

[mlp00]

You can only reduce CYA by water dilution. I'd just live with it since it isn't terrible and will slowly get oxidized by chlorine at the rate of around 5 ppm per month (maybe somewhat higher at your current CYA level). Up to you though -- you can go down just to 40 ppm if you like.

If you won't be soaking every day, then carefully measure your 24-hour FC loss rate. If it's high like 50% or more, then you probably have a functioning ozonator while if it's low at less than 25% then your ozonator may not be working.

You'll want to get your TA lower closer to 50 ppm before you add the boric acid (perhaps to 60 since the boric acid will be slightly acidic).

Am I safe to move to Bleach then even with my current higher CYA (once boric acid arrives and I drop TA closer to 50)? If so, do you think I should adjust the 3.5 oz of 8.25% Bleach / per person-hour rule to account for the higher CYA, or just stick with that formula while the excess CYA works its way out?

Thanks for the FC loss rate suggestion. Currently, we are still using the tub almost nightly but will try to arrange for some downtime to get some careful measurements.

[chem geek]

Yes, you can move to bleach since your CYA isn't terribly high. Remember that most people use Dichlor-only which keeps building up the CYA level higher and higher, though after it gets over 100 or 200 ppm that's when we've seen more reports of hot tub itch/rash/lung.

You don't change the per person-hour formula. That's the amount of oxidizer needed to oxidize bather waste and is independent of the CYA level. The higher CYA will make that process slower so if you were to soak frequently back-to-back such as twice a day you may get behind or if you soak every day with high bather loads you may get behind (i.e. have a buildup of bather waste yet to be oxidized and perhaps also a buildup of combined chlorine).

Worst case, if you find you aren't able to oxidize the bather waste quickly enough, you can do a partial drain/refill to get the CYA lower, but I think you'll be OK with where you are at. Certainly you can try it out first.

[mlp00]

Understood. That all makes sense.

I was able to check FC / pH this morning. At 10:20 AM (~14.5 hours since adding the Dichlor last nite) levels were:

FC 11.8

pH 7.6

CC 0.8

Does this remaining FC seem high or has it just not had enough time to oxidize? Cumulative amount should have been ~19.3ppm post-Dichlor last night of which I was expecting ~17.5ppm (2.5 * 7ppm) to have been used but maybe I need to get a reading closer toward the 24 hour mark (we won't be using the tub tonight). Because this was inclusive of bather waste, I suppose it won't provide the most useful idea of CD, will it? Maybe a FC reading tonight around 6pm and tomorrow around 6pm after 24 hours of non-use will be more useful?

[mlp00]

Understood. That all makes sense.

I was able to check FC / pH this morning. At 10:20 AM (~14.5 hours since adding the Dichlor last nite) levels were:

FC 11.8

pH 7.6

CC 0.8

Does this remaining FC seem high or has it just not had enough time to oxidize? Cumulative amount should have been ~19.3ppm post-Dichlor last night of which I was expecting ~17.5ppm (2.5 * 7ppm) to have been used but maybe I need to get a reading closer toward the 24 hour mark (we won't be using the tub tonight). Because this was inclusive of bather waste, I suppose it won't provide the most useful idea of CD, will it? Maybe a FC reading tonight around 6pm and tomorrow around 6pm after 24 hours of non-use will be more useful?

I checked FC @ 8:20 pm and it was 8.8. Our plans had to change and we ended up using the tub. With the CYA levels, we soaked about an hour later for ~2 person-hours without issue after which FC was 6.2, CC 0.8, pH 7.9, CYA 91 (from the Dichlor blast last night I guess?). I added 4 oz 8.25% bleach at 11:15 pm.

Will check everything tomorrow AM around 1030 am roughly 12 hours after last soak.

[mlp00]

I was only able to check via strip this morning and the FC was still 8-10+. I'm paranoid now of the CYA levels and will be doing a partial refill this evening and start again. Everything was great before the CYA got out of control!

[mlp00]

Did a water replacement tonight. It seemed like I swapped a lot more than I (apparently) did. According to Poolcalc, with my CYA now at 53 ppm I only replaced ~42% water. At any rate, after refill, my readings at 96 deg are:

FC 3.0

CC 0.6

pH 7.8

TA 70

CYA 53

CH 110

Inputting this into Poolcalc at 102f gives me -0.07 CSI.

Chem geek: My boric acid should arrive tomorrow. When I input the same stats but with 50 ppm borates and 50 ppm TA my CSI drops to -0.46.

Do you have any recommendations for me based on these current numbers?

[chem geek]

So the higher CYA level would slow down the rate of chlorine oxidizing the bather waste. With your now lower CYA the chlorine should react more quickly.

A low CSI in an acrylic spa is not a problem so long as your pH doesn't get low. A balanced CSI is for protecting plaster surfaces. Metal corrosion has more to do with low pH and strong oxidizers than with CSI. See the discussion in this link.

[mlp00]

Excellent. Thanks so much for your help through this. My borates didn't arrive today. The mailman said they could not deliver my parcel because the "receptacle was blocked". My neighbor's empty trash can was partially in front of my mailbox because it was trash day.

At any rate, FC is behaving a lot nicer with the lower CYA and I should be dropping TA and putting in the BA tomorrow evening.

What a great forum

[mlp00]

Borates went in today! Hooray!

I hope I calc'd it correctly. I added 92 tsp of boric acid based upon necessity of 13 oz by weight to reach 50 ppm borates in a 334 gallon tub where 1 tsp volume = 4.0g weight.

This went in just over 7 hours ago after dropping the TA slightly. Readings as of 12:20 am (45 mins ago) were TA 60, pH 7.6, FC 1.2, CC 0.4. I'm feeling very hopeful in all of this!

I've found my CD has been ~0.111 ppm FC / hour on idle but I'll continue to check this. I can certainly begin to appreciate the overall simplistic nature of it all once things are honed in. One day I hope to reach Tub Zen. You've been a tremendous, helpful resource. Thank you for your contribution to both this thread and these [and other] forums, cg.

Cheers!

[chem geek]

Your welcome. It does get easier once you're dialed in and figured out the chlorine demand and other characteristics of your spa.