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Thread: New spa. Chem nightmare Revisited.

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    New spa. Chem nightmare Revisited.

    Ok, the new spa will be here in a couple of days. Everyone has eased my mind a bit on the whole "chem nightmare" thing. I am going to try the BBB method first. I have a TF-100 test kit on the way. I also bought the chems to go the bromine route later on if I don't like the BBB method. I have been told that with my small tub (270g), borates to 50ppm will work wonders. I have a few questions...

    How much borax do I need to add initially to get to the 50ppm level?

    I plan on keeping the spa in my basement. Do you think I will have to worry about moisture causing mold and mildew? The reason I ask is, one guy on another forum said he would be worried about mushrooms growing from the ceiling. I do have a dehumidifier I can run during the summer and fall. I'm not so much worried about the colder months because I heat with a large wood furnace and the air gets very dry if I don't run a humidifier, so no worries in the colder months.

    Thanks for all of the help. I am more confident that I will be able to get the tub in check.
    21,000 in-ground with 60sf Jandy DE filter, Pentair Variable-Flow pump, Goldline Aquarite SWG.

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    spishex's Avatar
    Join Date
    Oct 2008
    Hillsborough, NC

    Re: New spa. Chem nightmare Revisited.

    Keep it covered and you'll be fine with it indoors. It would probably be a good idea to run the dehumidifier during and after use.

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    JasonLion's Avatar
    Join Date
    May 2007
    Silver Spring, MD

    Re: New spa. Chem nightmare Revisited.

    You can use my Pool Calculator, see the link in my signature, to figure out quantities. Simply enter the number of gallons in your spa at the top, then go down to the Borate section, a little more than half way down, enter 0 as the Now value and 50 as the Target level, hit tab and read out the amount of borax required.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

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    Re: New spa. Chem nightmare Revisited.


    I have a few suggestions, that might help make your adventure easier.

    1. Test the TA, pH and CH of your tap water. Then you'll know ahead of time what you'll need to do to balance your water. If your TA is high (>100 ppm) then you're going to need to get that down first. I recommend bringing it down to around 80 ppm for now. Later when you start using bleach, you'll want to lower even more to 50-60 ppm.

    2. Keep in mind, that you will need to add Dry Acid to counteract that Borax. If you don't, your TA/pH will rise way too high. What you can do is add the Borax to a bucket of water. For a 270 Gal spa that's ~16 oz according to the ThePoolCalc. Then add ~10 oz Dry Acid. Mix it up well and pour it into the spa. This mixture should be pretty close to pH balanced. You can check the pH to make sure. After you pour it into the spa, let the jets/air run for 20 mins then check your TA/pH. Adjust your TA back to around 60-80 if needed.

    3. If #2 sounds like too much trouble, you can buy a product called Gentle Spa. It will add Borates to your tub and is pH Neutral. You can also buy the pool version that should last you for years.

    4. You will be adding a total of 2 oz (12 teaspoons) of Dichlor to your tub before you switch to Bleach. This will give you around 30 ppm CYA. After you fill your tub, and get the water balanced, shock the tub with 4 teaspoons of Dichlor (10 ppm FC). Let the jets/air run for 20 mins, cover and let sit the first night. I know it may be difficult, but don't use the tub. Let the Chlorine sanitize the tub for 24 hours. The next night, the tub should be ready to go. Keep in mine, the FC will be a little high (~7 ppm), and the CYA will be a little low (~10 ppm), so the Chlorine may be a little strong that first night. It will get more mild as your CYA builds up. Keep track of how much Dichlor you add to your tub the next few days (week), because after you add 8 more teaspoons (a total of 12), you'll then switch to bleach.

    5. Once you switch to bleach, lower you TA to ~60 ppm if it's not already. The only thing you need to test regularly at this point is your FC and pH. Check FC before and after EVERY soak. If it's ever <1 ppm, you need to bump up the amount of Chlorine you use after soaks. Check pH after soaks (before you add Chlorine). If it's ever >8.0, add a little acid to lower TA (~50 ppm). At this point you should be well tuned and having no troubles keeping your tub maintained.

    6. Eventually you'll get to the point where: You'll only need to check pH once a week. You (or your wife) will know exactly how much bleach to add after every soak, (or every few days if the tub is not used). It will be so easy, you'll wonder what all the fuss is about.

    Good luck and keep us updated.

  5. Back To Top    #5

    Re: New spa. Chem nightmare Revisited.

    OK. Thanks again for the help. I have well water and I don't want to put that in the tub. I have a 210 gallon tank I use to haul city water and that is what I will put in the tub. Dry Acid - where can I get this cheap? I have some stuff labeled PH Decreaser, I suspect is will do the same thing as the Dry Acid? I saw some PH Decreaser at Walmart, but it wass in the pool section, is this the same stuff as well? Sounds like I will only need to through in a few ounces of bleach after each use or every few days of none use to keep it clear and safe. Thanks for the words of encouragement.
    21,000 in-ground with 60sf Jandy DE filter, Pentair Variable-Flow pump, Goldline Aquarite SWG.

  6. Back To Top    #6

    Re: New spa. Chem nightmare Revisited.

    If you have H*ll (I mean Well) water, it's good you have the option of hauling water in. If you have a water softener, you can use the water coming from that to top off the tub. Keep in mind it will filter out Iron and Calcium.

    Like I said in #1, check the pH, TA and CH in that city water asap. The further TA is above 80 ppm, the longer it will take to balance your water. If your source water's TA is 80 or less, you'll need very little acid. Just enough to counter balance the Borax.

    Yes, pH Decreaser is Dry Acid. That's what you'll need to lower TA. In a 270 gal tub, 10 oz dry acid will lower TA by ~100 ppm.

  7. Back To Top    #7

    Re: New spa. Chem nightmare Revisited.

    I won't be able to test the city water until I get a tank full at the bulk station. I think a quarter gets me 25 gallons and I don't want to get soaked by that 2" hose just to get a quart. I should have enough chems on hand to handle everything.

    Can I test the water when it is cold? It will take about 24 hours for the water to get up to operating temps.
    21,000 in-ground with 60sf Jandy DE filter, Pentair Variable-Flow pump, Goldline Aquarite SWG.

  8. Back To Top    #8

    Re: New spa. Chem nightmare Revisited.

    No big deal. I just thought if it were easy to get a sample, it will make the process go faster for you. It shoudn't take long anyway. I balanced a friend's tub with well water (TA=430ppm) in just a few hours.

    Also, you can test it when it's cold, it won't matter.

    Keep us updated.

  9. Back To Top    #9

    Re: New spa. Chem nightmare Revisited.

    One other piece of advice is test procedure for CH to get more precise value (since this is critical in water balance as well as PH and TA).
    When adding the R-0012 drop wise to get the solution color from red to blue - make sure you swirl for at least 20 seconds in btw drops.
    When a added multiple drops in btw shorter mixing times, I got a much lower reading, than what it was in reality.
    Sundance Hot Tub 365 gal, acrylic
    (2) 2.5 hp pumps
    Northwest Ohio resident

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