Combined Chlorine and MPS?

[jm_bc]

Hello All-

I've got a question about CC and MPS use - I have soft-sided spa ("Softub" brand - 220 gallons) that I have set up according to Nitro's chlorine method - the only major difference is that I added 30ppm CYA as dry stabilizer separately after my fresh fill and used bleach right away. I've been getting some stinging Chlorine smells coming from the spa recently, and we've been experiencing some pretty nasty itching after getting out and drying off. Thankfully no rashes yet. Last night I did a full slate of tests with my K-2006 kit and got the following:

FC: 5.5
CC: 1.5
PH: 7.6
TA: 60
CH: 140
CYA: 30 (based on amount of dry stabilizer added on fresh fill & no new water has been added to it yet)

Last night I added some more chlorine to bring the spa to shock level in the hopes that it would get rid of that CC.

The CC reading certainly explains the heavy stinging chlorine smell coming from the water - it was a surprise to see it that high so I started doing some digging around and have been reading lots about MPS and its benefits for breaking down organics (We have two kids 5 & 7 so likely getting some additional "contaminants" beyond typical sweat etc). This morning I went out to my local spa store and got a product called "Dazzle Amaze" which as far as I can tell is MPS though it's not specifically stated on the bottle. It is a non-chlorine shock product. When I got home I took off the cover and turned on the jets (no air) and added 48g (~1.7 oz) of the MPS.

Current reading about 2 hours after adding it is FC: 9.0 & CC 1.0 but I understand MPS can interfere with the CC test so not sure I trust it. I've popped the lid back on and am letting it come back to temp before we get in to test the itch factor. Any advice you can offer as to whether CC was the issue or if I'm missing something else would be greatly appreciated. Additionally, I'm hoping some advice on MPS dosing and levels moving forward could be shared.

I'm hopeful this awesome community of knowledgeable people can help me out! Thanks!

Josh

 

[YippeeSkippy]

MPS will read as CCs.

Are you opening the spa and letting it air out for about 15 min before getting in? That should take care of some of the trapped gasses under the cover which will smell strongly of chlorine.

Powdered CYA is fine, that's what i use too when doing a fresh fill.

Maddie

 

[jm_bc]

Hi Maddie-

Thanks for the reply! Does MPS read exactly as CC's? For example, if I am getting a CC reading of 1.0ppm, does that mean I actually have 1.0ppm of MPS or is there a conversion rate to factor in?

We are opening the cover 5-10 minutes before we get in but we were still having the heavy stinging chlorine smell after almost an hour in the spa!

I'm happy to say that after using the MPS we are now getting back to better water conditions and less (but not yet eliminated) itching - I have been using approx 12g (0.4 oz) of the MPS after we get out of the spa each time and I seem to be able to keep an MPS reading of 1.0ppm before we get in for the next soak. I'm also working to keep the FC level at around 4.0ppm, testing this just before we get in also.

Still curious to see what dosing others are using of MPS on a regular (daily?) basis... Also, is a reading of 1.0ppm for residual MPS in the desired range?

Cheers, Josh

 

[YippeeSkippy]

Josh, yes, I *believe* the MPS does read as CCs although I've never heard of any one measuring MPS for any reason or if even possible? If you had CCs *and* MPS I don't know how you would determine it.

I don't know what else to tell you but it sure seems like that FC is too high! That sure could make your skin dry out and itch, IMO.

Maddie

 

[jseyfert3]

Josh, yes, I *believe* the MPS does read as CCs although I've never heard of any one measuring MPS for any reason or if even possible? If you had CCs *and* MPS I don't know how you would determine it.

I don't know what else to tell you but it sure seems like that FC is too high! That sure could make your skin dry out and itch, IMO.

Maddie

Taylor makes an MPS deox regent (R-0867) which gets rid of the affects of MPS. By using this, you can measure FC, CC, and MPS levels seperately. They make an add-on kit (K-2041 or K-2042) for any FAS-DPD kit which comes with the R-0867, a dropper, and instructions.

Also, I'm new here too, but 5.5 ppm fc is at the upper end of the 4-6 range recommended for 30 ppm CYA, right?