Question about shocking

[KristiS]

Hi everyone! I've had a pretty good year so far with my pool, however went on vacation and didn't have anyone take care of it for a week. Yes, I know...lesson learned. Anyway, I started shocking my pool at a level of 20 b/c my CYA is 50. I checked it every hour and kept adding bleach when it would drop at all. That was yesterday. Here are today's FC results:

8 am: 14.5 I added a gallon.
Noon: 15.
2:30 pm: 14.5
6:30 pm: 12.5

It is HOT and very sunny here today. Obviously, I'll lose some FC to the sunlight, yes? But is that too much? Every hour the pool is getting clearer and I can see the bottom. It's almost sparkling blue. The filter has not been dirty since this a.m. and at that time it was a cloudy white. Yesterday, it started green. My question is, should I continue to add bleach to keep the FC up, or should I let it go for the night and test it tonight and then tomorrow morning to see how much I've lost? I just don't want to get behind and have all this work be for nothing.

Also, at what level is it safe to swim? Half the reason I'm hesitating to add more bleach is b/c my kids (teenagers) want to swim.


Thank so much for your help!!

Kristi

 

[reebok]

are you keeping it at 20 when you test throughout the day? anyway, shocking is a process. tonight you should raise to shock level, test in about 30mins and then test in the morning to measure any overnight loss. remember to keep the pump running.
pool-school/overnight_fc_test

 

[frustratedpoolmom]

If you want to let them swim tonight, just add more bleach tonight when their done swimming.

 

[KristiS]

I kept it at 20 all day yesterday, but today you've seen my results. I know you are supposed to be "in the clear" and can stop shocking when the FC doesn't go down more than 0.5 per hour, correct? Or 1.0 overnight. It just seems like I'm losing a lot less FC today than yesterday, so I guess I was hoping that I didn't have to keep it at 20 all day again today. And I haven't. With the filter being almost clean and the pool almost clear, I was hoping that meant I had beat it and I can let the filter do it's job and clear the pool. I still have about 12 containers of bleach (96 oz, 6%) but I was hoping to keep that on hand and not have to keep adding it. I guess I'll just raise to 20 tonight and do the overnight test and go from there.

My Ph is a bit low...at what point do I raise that? I remember reading somewhere that the ph reading is sometimes different when shocking, but I don't remember the specifics. Off to look for that now.

Thanks again!

 

[frustratedpoolmom]

If your FC is above 10, the PH will read a false-high, so it's best to adjust PH when the FC is below 10.

 

[reebok]

that's a good way to shoot yourself in the foot. hopefully it is all dead, but you don't meet any of the criteria to be sure you're done shocking. one of the criteria is .5 or less cc's. I haven't heard of the .5 fc loss per hour you mentioned.
if you want to post your ph you can probably get advice. what you're looking for is the ph reads falsely high when the fc is >10ppm.

 

[frustratedpoolmom]

Me either. The criteria is 1ppm overnight loss, .5 CC or less, and sparkly water.

 

[KristiS]

My bad. My CC reading is 0. So I do meet ONE of the criteria. I was thinking a 0.5 loss of FC. Oops! I do understand all this...it just gets a little jumbled as I really haven't had to shock since last year when I started on here. I test daily and add bleach as needed. Love this method.

Well, I think I'm almost there. Thanks FM for the Ph clarification.

The kids decided not to swim so I just raised to 20, I'll check before bed and in the morning before the sun hits it. Keeping my fingers crossed.

Thanks!