timDIDit

Tim, CYA is not added separately to chlorine in Dichlor (or Trichlor) -- it is part of the chemical compound itself. So while different products might have different concentrations of Dichlor, the amount of CYA added per FC added will always be the same for any product. Usually, most dichlor products are nearly pure anyway, but perhaps your non-SpaGuard products are "cut" and are not pure Dichlor, but then you would need to use more of them to get to the same FC level. SpaGuard is dichlor dihydrate as are most Dichlor products (there might be some that are anhydrous, but usually not since it's more of a fire hazard). The Total Dissolved Solids (TDS) are irrelevant for the most part. They are mostly salt, especially if you switch to using Dichlor-then-bleach. You can go longer than 3 months if you wanted to and still be under 2000 ppm salt at 6 months if you use less than 7 ppm FC per day (about a person-hour of soaking). Richard This whole discussion has been tremendously helpful! Since I last posted, I pumped out about 70% of the water in my spa, and refilled. I adjusted the chemistry to get it where it belonged, and have since been using Clorox as the sanitizer. Both of us were having "spa itch" problems due to the high CYA levels. Now that CYA is down near 50, all irritation has stopped, and the spa water has a better "feel" as well as a better smell - a win-win sitation! I probably should have pumped a bit more water out (or perhaps just drained and changed) in order to get the CYA level closer to 30, but that can wait for another day. Tim/

Rite, really helpful... Put like this: Those of you who use chlorine in any form, do you remove pillows and leave cover off after adding chlorine / bleech? /Z I leave everything in, HOWEVER, I "only" get about 3-1/2 or 4 years out of a set of pillows and cover. They get pretty "shrivelly" as time goes on. Hot Spring charges a fortune for pillows, but I still feel it's not outrageous to replace them every so often. Tim/

Your CYA level is probably so high because you've been using diclor (chlorine granules) or triclor (the pucks that are typically used with a floater). These chemicals contain a lot of CYA which, at high levels like yours, interferes with the sanitation process. Lastly, I think you are just guessing at your CYA level (120-150). It could easily be over 200. Let me explain ... I think I have the same Taylor kit and it only measures CYA up to 100. If you look at the marks on the cylinder, you'll see that they get closer and closer together at they approach the bottom. It's a logarithmic scale. It's not linear and therefore it's almost impossible to "eye ball". You can get a more accurate measurement by diluting the test water and then multiplying. Anyway ... this is another reason to dump ALL the water in your tub. If your CYA is really 200, getting rid of only half of it will bring it down to 100 which is still too high. Good luck, - Simon Personally, I would be itching like crazy if my CYA went that high! I can almost tell without testing when CYA levels pass thru 150 or so - I get a terrible case of "hot tub itch!" I have changed to a dichlor-then-bleach regimen, and it seems to be working fine.

Tim, Can you be more specific as to when you begin to suffer hot tub itch? Do you know how much cumulative Free Chlorine (FC) you've added by Dichlor, both regular addition and by shocking, when you begin to suffer hot tub itch? We've never really gotten a good handle on this, though it seems to occur somehwhere in the range of 1-2 months of Dichlor only use which would be around 100-200 ppm CYA at usual Dichlor dosing levels. Richard I have not conducted an accurate study, but I'm going to guess that right about the time CYA hits 150, the itching starts. That would be between 1-1/2 and 2 months for me, depending on how much dichlor I have added. I have also noticed that the brand of dichlor I use makes a big difference. I have completely stopped using SpaGuard products, as they all seem to be loaded with CYA. Most of the other leading brands seem to have less. Maybe it's just my imagination, but I know that whenever I used SpaGuard, my CYA levels increased much sooner, and to a higher degree. I generally change my water every 3 months, and it is still clear and odorless at that point, just loaded with CYA. In any event, I don't like to go longer than 90 days, as the dissolved solids start to increase, and I like to keep them down as well. Tim/

Thanks, NewB! That makes sense, and probably accounts for the fact no one has come forward with a direct equal. I have a full Taylor kit, and had planned to monitor the FC that way, regardless of what info I gained during my research. Interesting that there is no longer a need to shock. Am I to gather that when Clorox depletes, it leaves no chloramines? Tim/

I have a Hot Spring Vanguard, which has been very reliable. It's about 7 years old now, and so far has had two heaters (one on warranty) one new circulator pump (under warranty) one new heater relay board, two covers, and about 4 sets of filters. Given the amount this tub is used, and the pleasure we get from it, I'm completely satisfied! Tim/

This topic is of great interest to me, as I suffer from "hot tub itch" just as soon as the Cyanuric Acid number goes up. Accordingly, I have been looking for an alternate chlorination method to dichlor, and I believe that Clorox may be just the answer! This may be a silly question, but I have never seen any specific numbers mentioned with regard to how much Clorox needs to be added, and how often. My tub bather load is pretty consistant at 2 people for one hour per day. The tub is a Hot Spring Vanguard with a capacity of 400 gallons. For the last couple of years, I have found that adding one tablespoon of dichlor per day, plus three tablespoons once a week to shock, keeps my water clear and odorless. The only thing that does get out of control is the CYA. Assuming I start with dichlor, let the CYA build up to 30 ppm, THEN switch over to Clorox, what would be the equivalent "dose" of Clorox versus one tablespoon of dichlor in my tub? Thanks! Tim/