Help w/ TA rising please!

[lka674]

FC = 6
CC = 0
pH = 7.5
TA = 50????? down from our normal of 60
CH = 490
Temp = 77

Any help is much appreciated here. We live in TX...just got our first consistent drop in temperature this past week.

We had a TON of rain last week, which I know is the reason the TA has dropped from where we keep it (60 due to the fact that our pool gets 100% sun exposure all day), but I've added the pool calculator's recommended dose of baking soda now twice and it has not budged the TA at all. We are aware of the high CH, but we are maintaining it by keeping the CSI below 0 at all times.

I just don't understand why the TA won't come up at all. We did have to drain off quite a bit of water after all of the rains...and we do get some evaporation, but it's minimal so the auto fill isn't dumping a ton of water into the pool either....

Suggestions would be wonderful!

Thanks!

Laura

 

[duraleigh]

I can't answer why you did not have initial success with the baking soda but it's the right treatment. Test again and dose again.

Be sure to take the test completely to it's endpoint.....no further color change.

 

[lka674]

Ahhhh....that might be the key. I've never taken it to it's end point....did not know to do that! I've always stopped as soon as it turned from purple to a shade of pink. If I do add another drop it becomes an even darker shade of pink and then no other change takes place...which would bring us to 60.

So, here's the new question....if I've NEVER taken it to it's end point before, do I assume I've never actually been using the correct TA? If that's the case....what I've always thought was 60 was really 70....because an extra drop always would make it a darker shade. Hmmm...

Am I correct with where I'm trying to keep it then? 60 as opposed to 70 because of the amount of sun and b/c I'm trying to keep the CSI negative to counter the CH?

Wow! Thanks so much for your reply....I've just been pool schooled...again! Love it! :-D

 

[duraleigh]

All of the color change tests need a specific endpoint.

Count the drops until the very last drop makes absolutely no further change. Then subtract that drop from the total and you have the correct result.

I am personally not a big fan in a really precise TA. Each pool seems different. 60 or 70 either one should not have much affect.

That said, we do teach precision and your test is capable of providing it so set it where you want and observe if your pool seems to be happy. If so, then leave it.

 

[Patrick_B]

Dave is right on all counts. You do need to reach the end of all tests by being sure the change is complete.