Slam Question re CYA and Chlorine Addition

[bobwatson]

Starting up and we need to SLAM. Our CYA is 0. So two questions for guidance:
1. To raise the CYA is there a top limit of how much of the Clorox CYA to add at one time - or use the entire amount of CYA as recommended on the label for the water volume of the pool.
2. Can I add a limited amount of chlorine during the period I am adding the CYA prior to reaching the recommended CYA level?

Thanks.
bw

 

[Texas Splash]

Hi Bob and welcome! Your situation requires a bit more info to assist you. Here's what I would recommend:
1 - Note - Do NOT add any stabilizer yet. Use regular bleach (NOT Clorox brand either-polymers) to increase the FC to "10". Don't use the label, use our PoolMath tool to calculate how much to add. Once you add to make FC to 10, test again in 10 minutes. If it's holding between 5-10, good - go to next step. If it fell drastically, increase FC back to 10 and re-test again in 10 minutes until it starts to hold.
2 - Once the FC is beginning to hold, lower the pH to 7.2 with muriatic acid.
3 - Now ensure you have a minimum CYA of 30 and increase the FC to "12" your actual SLAM Process level. Test as often as needed to try and maintain that FC of 12 until you pass all 3 SLAM Process criteria.

Your TF-100 and the PoolMath will keep you straight. Good luck!

Adding CYA:
To increase CYA via granular stabilizer, place the required amount as calculated by the Poolmath calculator into a white sock and place in the poolside skimmer basket. For those concerned about suction flow to the pump, suspending the sock near a return jet or from a floating device will also suffice. Best never to allow undissolved granules to rest directly against the pool surface. Squeeze the sock periodically to help it dissipate. Once dissolved, consider your CYA adjusted to that programmed (target) level. CYA test readings should show a rise in 24-48 hours, however some pools may experience a longer delay to fully register. Best to confirm final CYA in about 5-7 days before adding any more stabilizer/conditioner.

 

[bobwatson]

Thank you, Splash.
On the go!

 

[bobwatson]

Hey Splash.
So this morning, we have the FC hanging on for the 10 minute period of which you spoke, even though the CYA continues at 0. So I conclude from that is that we will continue to slam targeting FC, but also adding stabilizer slowly as mentioned, sockful in the skimmer intake.
I also have very low pH = 6.8 (add borax) and TA = 20 (add baking soda). Shall I wait to correct those components till later in the slam, or do it now?

 

[Texas Splash]

You are correct about moving forward with the SLAM and adding the stabilizer. That TA and pH are certainly low though. If you're sure about those numbers, I would add some baking soda if you have it handy to get that TA up to at least 50-60. That increase in TA, along with the elevated FC level of the SLAM, should help to get the pH back into the 7s.