Newbie question....confused about alkalinity.

[Dragoth]

Hey everyone, new to pool ownership and the forum. First some background on my pool setup:

Intex above ground vinyl pool 12x24x52
Intex SWG

Set it up about a week ago. After filling it up, I shocked the water at the advice of the local pool shop, filled it with the proper amount of salt and ran the filter for 24 hours to get it all dissolved. Added the amount of CYA indicated in Intex's instruction manual based on my pool size a few days ago. Last night after my filter and SWG had been running for a few hours I tested my water. Not sure if that was a good time to do it or not.

I purchased a Taylor Test Kit 2500. My levels were as follows:

FC - 5
PH - ~7.4 (Still not sure what color of pink I should be looking for)
TA - 220
CH - Forgot to perform this test last night (it was late).
CYA - 50

Now I know PH is minutely low and CYA is low for a SWG pool. TA is obviously high and FC is good. The question is, should I worry about adding anything or trying to lower Alkalinity? I get the impression you only really need to worry about TA if it's causing a problem, but doesn't high TA reduce the effectiveness of the FC? Also, I know my CYA is low for a SWG pool, but I only added the stuff through a sock (it all dissolved out of the sock) a few days ago, should I wait and see if it goes up in a couple more days?

I'm having a "pool party" on the 4th and want to make sure I'm not going to have issues. The water looks clean and clear, although I have had a few Boatmen in the pool so perhaps I have some algae started that I can't see? This is all new to me so I'm learning as I go. Thanks everyone for any advice you may be able to give!

 

[JVTrain]

Welcome to TFP!

Alkalinity is one of the last numbers to concern yourself with once you have your other chemistry in line. TA is a measure of your water's ability to withstand changes in pH. The higher the TA, the harder it is to change the pH, intentionally or environmentally. With a higher TA, you'll usually experience a faster pH rise over all because high TA (carbonate ions, mostly) in the water makes carbon dioxide outgas faster (during any type of aeration). CO2 outgassing drives pH up. Lower TA = lower pH rise. TA level has no effect on chlorine's ability to sanitize.

If you're chlorinating with trichlor or dichlor, they are acidic. They will combat this pH rise but will insidiously add CYA to your pool over time if used regularly. The easiest advice is to just maintain your pH between 7.4 and 7.8 and each time you add acid, that brings down your TA.

Here is a guide to lowering TA more intentionally if you're experiencing fast pH rise and want to attack it, but usually not necessary. Pool School - Lower Total Alkalinity It's a process that takes several days to weeks, depending on how high the TA is and if additional aeration is used.

 

[Dragoth]

Great, thanks for the information. I was thinking that would be the best course of action at this point, (simply monitoring pH and adjusting it down when needed).

This site is great and I've gotten a lot of very useful information from it. I'm kinda going through information overload.

Thanks again for the reply.

Sent from my SM-G935T using Tapatalk

 

[JVTrain]

Great, thanks for the information. I was thinking that would be the best course of action at this point, (simply monitoring pH and adjusting it down when needed).

This site is great and I've gotten a lot of very useful information from it. I'm kinda going through information overload.

Thanks again for the reply.

Sent from my SM-G935T using Tapatalk

Glad you're enjoying the site. I understand completely about the information overload. I've been on the site for about 2.5 years and I still learn something new all the time!

 

[Chasmengr]

Good thread. I needed that TA-pH info, too. Thanks