pH keeps going up

[lucimireles6]

Hi all!

I recently finished SLAMing the pool, but my pH keeps going up quite high every day. I read on TFP that it's due to the high TA. I started with TA 300 a few weeks ago, and now I'm down to 200.

What level should I aim for? I've got a tiny AG pool - 5300 gal

I had a pH of 8+ day before yesterday, but 2 doses of dry acid got it down to 7.2 last night. It's 7.8 right now (the pump was running all night because my husband forgot to turn it off).

This morning's readings:
pH 7.8
CYA 40
FC 16.5 (it was up to 20 during shocking process, just finished 2 days ago)
CC 0
TA 200

We do not have a SWG right now.

 

[Azgirl71]

Your ph won't be accurate with your FC above 10ppm.

 

[Propbndr]

Recommended levels can be found here:

http://www.troublefreepool.com/content/134-recommended-levels

PH readings can be inaccurate (reading high) when your FC is above 10. You may want to wait until the FC is 10 or less and test PH again before making any adjustments.

(Azgirl beat me to the answer)

 

[Patrick_B]

That is correct. The pH reading is invalid above FC 10 and up. Don't adjust or retest until it's below 10 FC.

 

[pooldv]

Here is a little more detailed info on saltwater balance. Water Balance for SWCGs

 

[lucimireles6]

Oh wow.
Thanks! I can't believe I forgot that.

 

[lucimireles6]

Additional question: my pool is in direct sunlight all the time, so should I aim for a higher level of CYA? I read elsewhere that 60-70 might be better, even for a pool without a SWG

 

[JVTrain]

At that high TA level, your pH will also rise faster than with a lower TA. Once you can reliably test pH at lower FC levels, just keep dropping the pH to 7.2 when it gets above 7.8 and eventually the pH rise will slow once TA gets to a lower level through the acid additions.

 

[Patrick_B]

Additional question: my pool is in direct sunlight all the time, so should I aim for a higher level of CYA? I read elsewhere that 60-70 might be better, even for a pool without a SWG

Try it no higher than 60 for a while and see how that does. You can always increase it.

 

[lucimireles6]

I will! Thanks for all your suggestions

 

[lucimireles6]

At that high TA level, your pH will also rise faster than with a lower TA. Once you can reliably test pH at lower FC levels, just keep dropping the pH to 7.2 when it gets above 7.8 and eventually the pH rise will slow once TA gets to a lower level through the acid additions.

I will do that. Thanks!

 

[lucimireles6]

I turned the pump off this morning.
The FC dropped to 11.5. Is that typical? That seems like a huge drop. The surface of the pool is pretty warm since the water wasn't circulating. Should I leave it running and turn the filter off?