It is currently May 24th, 2012, 4:31 pm

All times are UTC - 6 hours [ DST ]



 Page 1 of 1 [ 5 posts ] 
Author Message
 Post subject: Lowering TA, Just making sure I'm doing it correctly.
PostPosted: August 24th, 2011, 6:44 pm 
Registered User

Joined: March 17th, 2010, 9:17 am
Posts: 78
Well my PH and TA have been getting high, so I've decided to do something about it finally. Ive never had to lower TA so i just want to check that i'm doing ti correctly. Today's test results were:

FC 5
CH 250
TA 250
PH 8.2
CYA 20

So according to what I've read, I've got about 4 gallons of MA, and the LPS told me to only dose about 2 qts at a time. I've made 2 DIY pvc aerators. I just put in the first dose of MA and i'm gonna wait about a half hour to check the ph again.

It's my understanding that i should only add more MA once the ph reaches about 7.6 again correct? Anything else i should know or am missing?



_________________
23000, Sand, IG, Plaster, Century Pool/Jetted Tub Motor 1.5HP, Rainbow Lifegard Feeder Model 300
Offline
 Profile  
 
 Post subject: Re: Lowering TA, Just making sure I'm doing it correctly.
PostPosted: August 24th, 2011, 6:53 pm 
Mod Squad
Mod Squad

Joined: July 30th, 2010, 8:56 am
Posts: 1747
Location: Minnesota
I am assuming you have read: http://www.troublefreepool.com/pool-school/lowering%20total%20alkalinity?

Basically use poolcalculator.com to calculate how much MA will bring your pool down to 7.2 pH. Then slowly pour the MA in front of the return. Aerate to raise pH up to 7.8, then repeat and lower to 7.2, repeat, repeat, repeat, until you reach your target TA level.

By the way, your ph is probably higher than 8.2 (limits of most tests), so your first dose may not lower as far as you are expecting.



_________________
Going to Pool School and learning the BBB method of pool care with a TF100 test kit that helps me use the Pool Calculator to properly maintain the water in my: Round AGP 11K gal (free on CL) with a deep end, Meteor 20" sand filter, Matrix 1hp 2spd, 4 2ftX20ft Sungrabber panels, Intex SWCG (copper bars removed), and Borates. Also a Rubadub hot tub and a UDS (Ugly Drum Smoker) poolside.
If your water has you worried, do an Overnight Chlorine Loss Test (OCLT), and if you fail, then follow the Shocking Process until:
1. CC is less than 0.5 ppm, 2. An OCLT shows a loss of 1.0 ppm or less and, 3. The water is crystal clear.
Offline
 Profile  
 
 Post subject: Re: Lowering TA, Just making sure I'm doing it correctly.
PostPosted: August 24th, 2011, 6:57 pm 
Lifetime Supporter
Lifetime Supporter
User avatar

Joined: January 6th, 2010, 10:54 am
Posts: 2464
Location: San Dimas, CA (LA County)
2 qts is barely going to touch things. And you may also be above 8.2 - that's as high as the tester reads. You could be at 8.5 or beyond!

Plug the numbers into Pool Calculator. All the numbers. It will give you the dosage to achieve the results you want. MA dosage will vary depending upon the TA level, so be sure to enter all the numbers. I recommend prediluting the acid in a bucket of water then pour it slowly in front of a return so it mixes fast. A few passes with the brush will also stir things up nicely.

When I went after TA, I dropped pH to 7.0, aerated it for a couple hours, then retested pH and plugged the numbers in to get back to 7.0. No point waiting to get up to 7.6 (You might not have to wait long anyway) as it works faster at low pH.



_________________
16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
Offline
 Profile  
 
 Post subject: Re: Lowering TA, Just making sure I'm doing it correctly.
PostPosted: August 24th, 2011, 7:02 pm 
Registered User

Joined: March 17th, 2010, 9:17 am
Posts: 78
ok great thanks for the help...

Just tested again and ph is at about 7.2, I'll just keep re-calculating and watching it. Seems as though you should add more MA as soon as PH rises back correct? No reason to wait 8 hours in between doses?



_________________
23000, Sand, IG, Plaster, Century Pool/Jetted Tub Motor 1.5HP, Rainbow Lifegard Feeder Model 300
Offline
 Profile  
 
 Post subject: Re: Lowering TA, Just making sure I'm doing it correctly.
PostPosted: August 24th, 2011, 7:11 pm 
Mod Squad
Mod Squad

Joined: July 30th, 2010, 8:56 am
Posts: 1747
Location: Minnesota
You can lower it more often if you are willing/able.



_________________
Going to Pool School and learning the BBB method of pool care with a TF100 test kit that helps me use the Pool Calculator to properly maintain the water in my: Round AGP 11K gal (free on CL) with a deep end, Meteor 20" sand filter, Matrix 1hp 2spd, 4 2ftX20ft Sungrabber panels, Intex SWCG (copper bars removed), and Borates. Also a Rubadub hot tub and a UDS (Ugly Drum Smoker) poolside.
If your water has you worried, do an Overnight Chlorine Loss Test (OCLT), and if you fail, then follow the Shocking Process until:
1. CC is less than 0.5 ppm, 2. An OCLT shows a loss of 1.0 ppm or less and, 3. The water is crystal clear.
Offline
 Profile  
 
Display posts from previous:  Sort by  
 Page 1 of 1 [ 5 posts ] 

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: Davsmth41, nfusion770 and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  


TroubleFreePool.com The Web