Post-hurricane SLAM: low CYA, can't pump 24/7, too little chlorine?

[feuGene]

I'm cleaning up after Hurricane Irma. My pool is under screen so there wasn't TOO much debris, but the power was out for about 4 days and the water was definitely dirty and gross. I got all the debris removed, filter cleaned, etc, and now I'm SLAMming.

(To complicate things, my CYA is low (reading between 50 and 40, a tad closer to 40), and there is no corresponding shock FC level listed on the Chlorine/CYA Chart, and my pool store is out of CYA! Going against the "not recommended" advice on that chart page, I decided to SLAM anyways, and I took the liberty of extrapolating from the (few!) values in the chart, figuring a shock FC level of 16.)

I went out and got 2 "gallon" jugs of bleach from Walmart (only 121 oz each!). I didn't realize how much bleach would be called for: when I went to shock, PoolMath called for 2.7 gallons, so I just went with what I had, which after a half hour put me at 10FC/0.5CC. Two hours after that I was at 8.2FC/0.2CC, and then I went to bed (read: it was dark out). First thing this morning (dusky but before sunrise) I was at 6.6FC/0CC, and two hours later 6.4FC/0.2CC. (That last CC reading could even be zero, depending on my level of color perception. If there was any pink, it was VERY VERY slight.)

I realize that I PROBABLY never reached the shock level. (The Chlorine/CYA chart is non-linear so who knows.) But the thing is, right now I'm pretty happy. My CC is low if not zero, and the water looks great. I would just stop now, except that I "failed" the overnight FC loss test.

Also complicating the process is the fact that I'm having trouble getting my pump to run 24/7. Two nights in a row now I go to bed and it's running and I wake up in the morning and it's off. Yesterday morning I thought maybe an errant "Schedule" on my Easy Touch system was to blame, so I just deleted all the Schedules. This morning it's off again and I can't fathom why.

Is my whole process tainted because of my low CYA? Should I just stop the process and wait until I can fix my CYA level?

Is my overnight FC loss test result invalid because I never really shocked in the first place? Should I do an actual shock and then go from there?

Or should I just stop the process now because my water looks good and my CC is plenty low?

 

[mknauss]

Do not add any CYA! Complete your SLAM then manage that. Follow the non- SWCG chart. That is what you have during a SLAM. You are not maintaining with your SWCG you are adding liquid chlorine.

You will need at least 10 jugs of bleach. Test and dose every hour or two and keep at your shock level based on your CYA (you reported 50 - so 20 FC is your shock level).

Did you check your pH? Test it before adding any bleach. If necessary add muriatic acid to lower it to 7.2 and SLAM Process.

Take care.

- - - Updated - - -

Use the 10 ml sample for FC testing. You are going to go through reagents quickly. Do not test CC again until your water is clear and you plan to do a Overnight Chlorine Loss Test. That will no doubt be several days to a week from now.

 

[feuGene]

Thank you for the quick and helpful reply. I did balance my pH before starting, but only to 7.6, and I see now that's outside the bounds of the SLAM guide. I will carry on. Thanks again