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Lowering Total Alkalinity

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2 hours ago, tsharpe82 said:

I don't know what I'm doing wrong but I cannot drop my TA.  My TA is 180+ and every attempt at lowering it drops my PH way low.  Ive maybe seen around 125-130 at the lowest but my PH is then super low in the mid 6's.  When I raise my PH to 7.4ish my TA is again off the charts.  I'm using Spa up and Spa down but both seem to either drop or raise both TA and PH even after the aerating my ph is dropping with the TA.  My local spa dealer can't figure it out, they've done 4 empties and refills in the 6 months I've owned the tub.  I was using a Bromine system but switched to Chlorine Spa 56 for my sanitizer.  Any suggestions?

 

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I've aerated and aerated for days and I cannot get my PH to go up at all.  The only time my PH goes up is if I add Spa Up and then it sends my TA off the charts.  I try lowering the TA incrementally trying to get PH to around 7.  Then I try to aerate to increase PH before I drop the TA again with more Spa Down.  But the PH never ever goes up when I aerate.  I'm beyond frustrated.  I can get my TA down only if I keep adding Spa down but again it knocks my PH way down.  

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I haven't been able to lower the alkalinity AT ALL, despite adding a bunch of Alkanity & PH lowering chemical. Is it true that high alkalinity in the tub interferes with sanitizing (i.e., chlorine)? I'm ready to empty it and purge it and start again, but....how do I lower the alkalinity FIRST when the only chemical says it lowers BOTH?

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8 minutes ago, newguy2017 said:

I haven't been able to lower the alkalinity AT ALL, despite adding a bunch of Alkanity & PH lowering chemical. Is it true that high alkalinity in the tub interferes with sanitizing (i.e., chlorine)? I'm ready to empty it and purge it and start again, but....how do I lower the alkalinity FIRST when the only chemical says it lowers BOTH?

https://www.poolspaforum.com/forum/index.php?/topic/36290-lowering-total-akalinity-howto-not-just-for-pools/

https://www.poolspaforum.com/forum/index.php?/topic/28846-lowering-total-alkalinity-howto/

 

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I have been trying to balance my total alkalinity for days now. I keep adding dry acid first in order to lock that in. Once stable I try to add some PH up (because my ph is so low) and of course that also raises my TA!

What am I doing wrong? Is there not a product that ONLY raises or lower TA? Is there a product that ONLY raises or lowers PH?

I have been using the LEISURE Time Spa Up and Spa Down products, however, now I see on the label it also that's it'll directly raise and lower the TA as well.

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15 hours ago, tiff.lane101 said:

I have been trying to balance my total alkalinity for days now. I keep adding dry acid first in order to lock that in. Once stable I try to add some PH up (because my ph is so low) and of course that also raises my TA!

What am I doing wrong? Is there not a product that ONLY raises or lower TA? Is there a product that ONLY raises or lowers PH?

I have been using the LEISURE Time Spa Up and Spa Down products, however, now I see on the label it also that's it'll directly raise and lower the TA as well.

read BOTH of these:

 

https://www.poolspaforum.com/forum/index.php?/topic/36290-lowering-total-akalinity-howto-not-just-for-pools/

https://www.poolspaforum.com/forum/index.php?/topic/28846-lowering-total-alkalinity-howto/

 

Once you drop the pH you need to aerate to bring it back up, not add a chemical to do so. The above links explain everyting!

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Will soon be doing a fresh fill on a new (to me) used fibreglass hot tub. Here's my starting water chemistry:

CH 160 mg/L

TAlk 114 mg/L

pH 7.8

Free Chloride leaving the water treatment plant is at 1.1 mg/L so presumably >1 when it reaches me.

Is the CH of 160 close enough or should I try to somehow lower it to at least 150 or less? If best to lower it, how should I go about doing that?

I understand the process of lowering pH to ~7 and aerating to raise pH and lower TAlk. Given the CH of 160 mg/L or whatever I can lower it to, what  final TAlk  concentration should I be shooting for? 60 mg/L?

TIA

 

 

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I have read through this thread and am grateful for the clarity it offers in balancing a new fill. My spa is 350 gallons. I DO use a Del Ozone MCD-50 ozone generator (operates with my 24/7 recirc pump, so I am using double check valves to restrict some of the gas, if that works. Hot Spring was reluctant, understandably, to give advice about an after market unit, not theirs). One post by Chem Geek asked if an ozone generator was being used, but after negative reply he did not discuss fuirther. I would like to know what  using an ozone generator affects in the attempts to lower pH and TA. My assumption is that the constant off-gassing of ozone into my water is causing my pH to remain over 8. I have not yet added 50 ppm Borates as recommended to buffer pH. I use bromine as my main sanitizer and add chlorine bleach after bathing and when the spa sits for a time to activate the bromine. The ozone has been great for clarity and  other than the high pH on Taylor test I feel my spa is well adjusted. Please fill in the gaps in my knowledge of ozone effect on my pH. As always, thanks to the chemists in the forum who give so much to us.

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Since 2014 I have been dealing with fill water having a 340 TA for my 1850 gallon Artesian Tidalfit swim spa.  The attempt to wrangle these values took days and as stated, settling for less than ideal results was the norm.  Finally, I found this excellent post on lowering TA.  AERATION is/was the answer.  Nitro, this tutorial on the subject is spot on, a text book worthy explanation along with an easy to follow example.  

Where do I give you FIVE STARS?  Many thanks from the bottom of my heart.  

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mrwrick, ok thanks, and for nowadays I just think about hot tubs pregnancy issue, and is it safe enough for ladies and women (being pregnant) to take their time in hot tubs or jacuzzi?... Or are there any time restrictions or recommendations about it? Would be really interesting to hear some opinions of experts from hot tub's field of business.

 

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On 7/18/2018 at 5:57 AM, tiff.lane101 said:

I have been trying to balance my total alkalinity for days now. I keep adding dry acid first in order to lock that in. Once stable I try to add some PH up (because my ph is so low) and of course that also raises my TA!

What am I doing wrong? Is there not a product that ONLY raises or lower TA? Is there a product that ONLY raises or lowers PH?

I have been using the LEISURE Time Spa Up and Spa Down products, however, now I see on the label it also that's it'll directly raise and lower the TA as well.

 

Try to add not so much of PH.

I mean portions should be smaller and equal.

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On 10/7/2013 at 7:56 PM, chem geek said:

You should add chlorine right away so that the water doesn't go south -- bacteria can grow rather quickly doubling in population every 15-60 minutes. Then you can adjust your TA as needed and the pH is adjusted after the TA is set.

The only issue with adding chlorine first is that you need some CYA in the water so you can easily accomplish both by starting out using Dichlor. Do not add bleach (or any other unstabilized chlorine) to the spa with no CYA in the spa (the only exception is with a decontamination procedure).

Is there any alternative things to replace Dichlor ?

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42 minutes ago, kattie91 said:

Is there any alternative things to replace Dichlor ?

No, not really. You CAN add CYA and bleach but the CYA takes quite a while to dissolve. Dichlor dissolves almost instantly and will raise CYA 9 ppm for every 10 ppm of Free Chlorine so it's a very fast way to get CYA into the water.

 

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