Bleach Is Not Working For Me. Going Back To Dichlor.

[watersentinel]

Chris if you aren't going to buy your salt system right away I think you'd have luck adding the mps after a soak instead of before. I am confused about the smell you are having and have never encountered this with the use of mps. Usually customers have this problem because of too little fc in the spa. There is alot written here so you might have already mentioned your fc levels. If not, what level do you keep your fc at and is it constant? I know there are people here trying bleach in their spas and I wouldn't be at all suprised if they had problems with persistent chloramines. You said you don't like mps because of problems testing your sanitizer. Mps shouldn't register as free chlorine only combined chlorine. If you are keeping your fc readings up and shocking weekly or using an ozonator you shouldn't have to worry much about cc reading interference. I hope you and your wife find a way that you can both enjoy your spa with no odor.

[Chris W]

I maintain my FC between 3 and 6 ppm. I test my Chlorine levels using the FAS-DPD test. When I was using MPS, I added it right after the soak in the evening and left the tub open to the air witht he jets on for at least 15 minutes before closing added chlorine the next morning and left the cover open for about 15 minutes again with the jet running, but no air. When I was using MPS, it did require much less chlorine, to maintain a proper residual, but as I said, the smell was much stronger. When using MPS, I use the Taylor interference remover kit in conjunction with my FAS-DPD kit to attempt to get accurate results. When I am using MPS, even with the interference remover, my CC reading quickly jumps to 2.5 ppm and slowly rises over time. Whe I use chlorine alone, the CC stays below 1 ppm. The biggest confusion I have with the MPS is when I try to use it as a shock rather than daily maintenance. After the shock dosage, my FC reading with rise to 20+ ppm FC and stay there for days even with no addition of chlorine. Only hours of aeration per day and lots of sunlight exposure will gradually bring the FC level back down. The entire time the CC level stays at 2.5+ and after the shock, the CC level is still 2.5+. The only way I was able to reduce the CC level was with a 30ppm shock with Chlorine which also took a couple days to come down, but I had the cleanest, most odor free soak I've ever had after doing the strong chlorine shock. The CC dropped below 2 ppm, but climbed up again after my 1st use of MPS. As I noted in another thread I have stopped uising MPS at this point and am using just chlorine and acid to maintin FC and pH. So far I am very happy, my CC is consistently below 1 ppm, but I do still have a slight chloramine odor at times.

I will probably get a SWCG for my tub at some point, but the Spa Pilot instructions calls for near constant use of MPS which has me hesitating.

At some point in the future I plan to try a combination of Bromine and Ozone and see if the wife's breathing is less sensitive to that combination.

BTW, throughout all of this, my water is always crystal clear and looks beautiful. Most people would say my water quality is far above average based on their exposure to public hot tubs, but that doesn't set a very high mark in my book.

Any input is welcome

Chris W