dashmer

Suggest you use the pool calculator effects calculator to figure out how much you need. It has both baking soda and borax options. https://www.poolcalculator.com/calculator/effects-calculator

There is no CYA in liquid chlorine (sodium hypochlorite). Liquid chlorine = bleach. You can use pool chlorine (higher percentage, stronger) or plain, unscented laundry bleach (weaker). 3 fl oz of dichlor gets you about 30 ppm CYA. So depending on your use, a week might be accurate. Just count the oz you put in. Yes, mostly bleach after that. Apparently CYA drops very slowly over time. I use about 1/2 oz of dichlor about once a month after hitting the 30 ppm. I target water changes every 4 months. Water is crystal clear from start to end. You do need to watch your pH when on bleach as it has a tendency to slowly walk up over 8 with time. You just hit the tub with 1/2 to 1 fl oz of dry acid (ph Down) periodically when the ph gets up there. This is why it is important to start with a lowish TA of 70 ppm to slow the pH rise.

The recommended range for free chlorine is 3-5 PPM. You are looking for a residual Cl in your hot tub the next day after your soak the previous day that is in this range or perhaps a little lower. For amounts you should use the pool calculator located here: https://www.poolcalculator.com/calculator/ You specify the gallons in your tub and it will tell you how much you need to add to reach your target. I made this chart to have handy to the tub that would help me know how much chlorine was needed after a soak (based on 360 gal): Have a look at the top left two orange charts. They tell me that I need to add about 10 ppm of Cl for a one hour soak for 2 people if a "cooler tub", say around 100 degrees. For a hotter tub (104) the chart says 14 ppm for the same soak. I use liquid pool chlorine (as my bleach, in the dichlor then bleach) so I take 10 ppm + 4 for residual (total 14 ppm) and I look in the orange columns on the right. When my liquid chlorine is new and at 10% strength, I would put 6.3 fl oz of it in the tub when I get out. If you are using Cl granules as in your picture above, 1 fl oz gives you 12 ppm Cl and 10 ppm CYA. All of my numbers are for a 360 gal tub. You should find your Cl in that 3-5 ppm range the next day. If higher or lower than that, you need to add more or less Cl when you get out on the previous day. Chlorine granules are referred to as dichlor. If you use just dichlor you will build up CYA really fast and will need to changed your water every month or so. That is why the dichlor then bleach method was created. You only use dichlor until you get to 30ppm CYA and then you switch to bleach (that contains no CYA). I am not familiar with the frog system and the information I am giving you does not have any other Cl sources. If you would like to try this method, you should remove your frog system. You need to read the section on setting up for dichlor then bleach as it requires your TA to be quite low. Good luck.

I am sure this must be a disappointing experience for you and your family. Sanitizer is critical to keeping your water safe and I am pretty certain you are not using nearly enough. Your tub also has a pH that is high and will limit the effectiveness of the chlorine. You should try to keep that in the 7.4 to 7.8 range. I check my chlorine daily (before use) and my pH weekly. TA and CH monthly if I think they may be off. Your bather load is very similar to mine. We add 10-15 ppm of chlorine after every soak. There are a few stickies at the top of this forum that you should read. The first is a process called decontamination. If you want to be sure that you have eliminated all of the bacterial you should try this process. After that, you need to balance your water and add and maintain your sanitizer. Many of the people on this forum, including me, use the "dichlor then bleach" process for sanitizer. It has many benefits but requires daily maintenance. Bromine is another alternative that is a little more hands off and we have a sticky that describes that process too.

Lets start with understanding a bit more about your tub's water. Let us know your pH, total alkalinity (TA), calcium hardness (CH). If you do not have a liquid test kit to measure these, take your water to a pool supply place and have them test it for you. Your skin problems (especially with 3 of you affected) is almost certainly caused by bacteria as a result of insufficient sanitizer and less likely to be the sanitizer itself. You mentioned your water was cloudy and smelly...this was a case of no sanitizer at one point for sure. How do you test your chlorine level? Do you test before you get in your tub? What is the level? A significant amount of chlorine is needed after bathing (as much as 7 ppm per bather hour) just to clean up (oxidize) bather waste. Whatever is left is used to sanitize the water. Your frog system may not meet this demand. You also mentioned that you did a disinfecting water change and line flush. What products/process did you use? Additional details will help us better understand what recommendations to make. Bottom line, you will need to get a better handle on your sanitizer, be it chlorine or bromine.

Hello, Suggest you have a look at the stickies in this forum for one called Decontamination. If you follow that process you should not have any issues after that as long as you maintain proper sanitizer levels. You should also incorporate a bio film flush at the same time with ah-some.

Yes, that is the same setup as mine. To aerate just run your jets on high with those air knobs fully open. I think your local guy is going to send you off on the pH and TA roller coaster. I would follow the direction in the sticky if I were in your situation.

pH decreaser or minus are dry acid so that will work...easier to deal with than the liquid stuff. Does your tub have air injectors with the massage jets? If so that is all you need. It is just to breakup the surface to permit exchange of gasses. PS...I also fill from a well but my well water is low in TA, pH and CH...need to increase all when I fill.

Here in Canada, my well insulated hot tub uses about a $1 a day in the summer when no heating is needed and it is just running a small circulation pump (24/7) and UVC light. Temp in the summer is set to about 98. In the winter, set to 101, it uses roughly $2.25 a day (really cold days more) when not used. With use the cost goes up to $3.0 to $4 per day, depending on how long the soak is and how much the massage pumps are used. We only adjust the temp seasonally and use the tub nearly daily. Not sure in your case, but my tub has a winter mode where it will run the pumps to prevent freezing in the equipment area if it detects low temps on the controller board.

The stickies at the top of this forum describe the process for lowering TA without dropping pH. In a nutshell, acid to lower both, aeration to raise pH.

Anyone else having problems with the new version of the Pool Calculator app on iOS? I have had nothing but trouble with it, the most frustrating aspect is that the free chlorine does not function at all (cannot select type of chlorine).

Save yourself a lot of grief by getting a good liquid test kit...otherwise you are really just guessing with test strips. Most people on this forum agree that the Taylor K2006 is your best choice. Money well spent.

I also have acidic water (6.6) with low TA (40is) and generally wait until the water warms up a bit before balancing. Your test kit may also have limits on accuracy at low temps. You dont need it all the way but 70 or higher would be preferred. You didn't mention what your TA is or how you are testing the water.

I understand that borates do have an additional buffering effect, similar to TA. With a TA of 48, I would not expect your pH to be running that high. Increasing TA will not really help reduce your pH. How old is your water?

Suggest you read the sticky in this forum on lowering the TA. There are good detailed instructions on how to do it. It takes some time but you will get there. https://www.poolspaforum.com/forum/index.php?/topic/19149-lowering-total-alkalinity/ You didnt mention what type of chlorine you are using. A TA of 100 or more may be too high to keep you pH down in the correct range. If you are using the dichlor then bleach method, you will want to be down around 70 or maybe lower.