Jump to content

High TA.


robquick

Recommended Posts

Hi,

I normally run my tub on liquid Chlorine however, I ran out a few months back and have been using Dichlor. I've been a bit slack with checking TA and Ph so completed a full test last night and noticed that the Ph was very low (6.8). I slowly increased the Ph up to 7.5 however, the TA has shot up to 125...........when running running liquid Chlorine I normally have the TA at 40. The TA is normally very stable albeit it normally rises slowly as the PH rises but is easily reduced by reducing the PH.

Where have I gone wrong ?

Does liquid Chlorine behave differently to Dichlor ?

Should I have air-rated the tub to increase PH rather than using chemicals which in turn have increased TA ?

How do I correct it ? Use PH reducer to bring PH AND TA down and then air-rate to push PH back up ?

Thanks.

 

 

Link to comment
Share on other sites

Dichlor is acidic, so it reduces pH and thus TA. Bleach / liquid chlorine is almost pH neutral.

Additionally, dichlor contains cyanuric acid (CYA). For each 10 ppm of chlorine you add with dichlor, you add 9 ppm of CYA. It doesn't take long with dichlor to put the CYA way too high. The CYA in a chlorine hot tub should be around 30 ppm, no more than 40 ppm. In two months of using dichlor, you could easily be well over 100 ppm CYA. See the Chlorine / CYA Chart to see what it means.

If you are not familiar with it, you should read the dichlor/bleach method in a nutshell sticky post above in this forum.

Link to comment
Share on other sites

Hi,

Thanks for the reply.

My TA was 125 so I used PH reducer to bring the TA and PH down. As it stands my TA is 90 and my PH is 6.8. I've tried aerating the water for about 2 hours now with every blower and jet on however, the PH has only moved to 7.0. 

Would you expect such a small rise in PH having aerated for 2 hours.

Is it a case of persevering, or am I doing something wrong ?

Thanks.

Link to comment
Share on other sites

  • 1 month later...

A TA of 90  is, by itself, perfectly fine, so what are you trying to achieve?   there's  nothing magic about the TA number itself if your water is balanced  or a slightly negative saturation index -- higher TA values of course will encourage pH drift, but if you don't have that problem why are you trying to reduce TA?  the more important goal is to maintain pH, and through experimentation you will find what TA values give you the best results. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...