Shocking Pool - First Spring Opening

[nupoolsoon]

This is our first spring opening our pool that was installed last summer.

The water looks very clear! Very happy with that. Yes, there is dirt on the floor and some worms and other little debris, but I will vacuum that later today.

We have a SWG, but not using it right now since we do not have the pool salt on-hand yet and want to get the water balanced first.

#'s yesterday were
FC4.5
CC 0
Ph 7.7-7.8
CYA 30
TA 50-60

I added 20ppm CYA this morning to bring to approx 50 and then added some bleach 1 hour later which will add another 4ppm or so.

My question is should I shock the pool regardless of how clear the water looks and that the test shows "0" CC.

If I shock, since we are not using the SWG right now, can I shock to Non-SWG levels which would be around 20 or so? How long will it take for the 20 shock level to drop to a level that is safe to swim? The water is only 58 degrees, but anxious to get the solar going to raise the temperature.

Thx.

 

[JasonLion]

If the water is clear, CC is 0.5 or lower, and your FC level doesn't fall right back to zero when you add chlorine then you don't need to shock.

 

[duraleigh]

since we are not using the SWG right now, can I shock to Non-SWG levels which would be around 20 or so?

You sure can but it's because your CYA is down around 30 and not dependant on the SWG running or not.

Take your CYA up to around 60-80 when you start to use the SWG.

 

[nupoolsoon]

Thank you. I am trying to refresh my brain with everything that I learned last year. It was a long winter here in NY.

My next attack then should be to lower my PH a bit since I have to increase my TA a little, correct?

Also curious, I read that CYA reading can be affected by really cold water temps, so I let me water come to room temp first b/f testing...any other tests that might be affected by mid-50 water temps?

 

[JasonLion]

You want to do FC, CC, and PH right after taking the water sample, before the water temperature changes or significant time passes. TA and CH are not affected either way, except that CH may require more swirling at colder temperatures. The CYA test is more reliable at warmer temperatures.

The order in which you adjust PH and TA isn't really all that critical unless you are making large changes. I would lower the PH to 7.5, remeasure the TA, and then adjust the TA based on that measurement. But you can do it in another order if you want.