New pool in Texas: dialing in the chemistry

[Dtkokay]

Our new 25K gallon gunite pool is filled with water and startup was yesterday. See my build thread in my signature if you‘re curious.

I have an inline chlorinator in addition to a SWG. With a Pebblesheen surface, I can’t add salt for 30 days, so I’m going to rely on tablets / liquid chlorine in the meantime. The builder added trichlor tablets to the feeder yesterday, and I added a gallon of 10% liquid chlorine for a jump start. We also added muriatic acid, liquid stabilizer, and calcium chloride yesterday.

Using my TF-100 kit, I had the readings below this morning:

FC: 3
CC: 0
pH: 7.4
TA: 170
CH: 150
CYA: 30
CSI: -0.23

Doesn’t look too bad, although I need to lower the TA and raise the CH. The CH is easy to add and I have the right amount on hand. To lower the TA into the right range, I need to add 4 gallons of 31% muriatic acid, per Pool Math. My plan is to add enough acid to drop the pH to 7.0, using Pool Math, then let it rise naturally with the plaster curing and turning on the waterfalls.

Any feedback on my numbers or approach would be appreciated. Thanks!

 

[Texas Splash]

Welcome to TFP! About your notes above .....

To lower the TA into the right range, I need to add 4 gallons of 31% muriatic acid, per Pool Math.

You might double check that first. In Poolmath I'm seeing that in a 25K pool, just over 3 quarters (not 4 Gallons) should lower the pH from 7.4 to 7.0. Please verify on your end as well. Everything else you said and have shown above seem well thought out. Maybe keep the FC slightly higher at about 4-5. Nice work!

 

[Dtkokay]

Welcome to TFP! About your notes above .....

You might double check that first. In Poolmath I'm seeing that in a 25K pool, just over 3 quarters (not 4 Gallons) should lower the pH from 7.4 to 7.0. Please verify on your end as well. Everything else you said and have shown above seem well thought out. Maybe keep the FC slightly higher at about 4-5. Nice work!

Gotcha. I was actually referring to 4 gallons lowering the TA from my current 170 down to the recommended 90, not the pH. But I don’t want to lower the TA all at one time because it’ll take the pH way too low. Sounds like I’m on the right track? And thanks for checking over my info!

 

[Texas Splash]

Sounds like I’m on the right track?

Yes. FYI - Here's the actual page about lowering TA: Lower Total Alkalinity - Trouble Free Pool

Remember though, for the first 30 days you actually want the CSI to be slightly positive to allow the plaster to cure. You may want to wait until you're past that 30 day mark to get aggressive the the TA. For now, just keep basic chemistry in check.