I have gone through the shock process two times this year

Jun 24, 2011
16
Montgomery, AL
Pool Size
39000
Surface
Vinyl
Chlorine
Liquid Chlorine
I have gone through the shock process two separate times this year. The first time everything went fine, but it got to the cloudy stage and after a week or so it was still cloudy, even with backwashing. I added Clear and Perfect clarifier and it royally messed up everything. The water didn't clear but actually started to go back towards green. Last sunday I began again. Raised the shock level to 28, somehow I couldn't get it to 30. Brushed twice a day, backwashing daily, running my Dolphin pool cleaner to get what I can't see at the bottom, and praying.

It's Saturday and I'm at the cloudy phase again. I have been at this stage since Wednesday. My FC was at 38 at 6:42 pm last night (a little before sundown) CC was 0 and FC at 36.5 and CC at 0 at 7:52 this morning. Everything is still cloudy. I know it takes sand filters up to a week to filter out, but what about the shock level. Do I stop adding bleach and let the FC come down to normal, or should I continue to add the amount of bleach I would for regular maintenance? I've searched, but can't find an answer. Plus, I really, really want the water to clear up more quickly and I ready in another post that someone with a sand filter added DE to the skimmer. What was that about? I have never read about that. What is the process, does it work, and could it work for me? I know people wanted to swim for Memorial day, but with it so cloudy and FC so high it's looking like that won't happen. :hammer: Help me or come shoot me, though I prefer the first.

@7:52 am
FC 36.5
CC 0.5
PH 7.8
ALK 90
CYA 80
CH 80 (person at the pool store said CH only really matters if you have a concrete/plaster or whatever kind of pool, not vinyl is that true?)
 

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Re: I have gone through the shock process two times this yea

Have you done an overnight FC loss test? See Pool School for instructions.

How has the filter pressure been behaving and have you been backwashing and if so how often? When the filter is working correctly you should see a visible improvement in the water each day. Have you been able to see any improvement day to day?

There are instructions on adding DE to a sand filter in Pool School. That can often help in this situation.

Pools with vinyl liners really don't need CH.

You shouldn't have anyone swimming if you can't see the bottom.
 
Re: I have gone through the shock process two times this yea

Your CH is fine for a vinyl pool.

Yes, you can try adding some DE to the sand filter.

Here are instructions from Pool School: pool-school/add_de_to_a_sand_filter

Hopefully you are backwashing your filter when the psi increases 25% over clean pressure psi.

Also, your CYA of 80 is higher than the recommended 30 to 50. However, it will come down with backwashing and water replacement.

p.s. We don't shoot our members :mrgreen:
 
Re: I have gone through the shock process two times this yea

My filter's pressure remains at 30 whether the pool is in use or not, whether the filter is on or not, so under normal conditions I backwash one to two times a week. Only once have I seen it move and that was during the first round of shocking (End of March) when I backwashed it went to 28. I was backwashing every two days, but just recently (since Wed.) switched to every morning, when I read that too much can't hurt. The water looks better, but only minimally, I think that is why I am so confused.

I've done the overnight test a few days ago and it showed CC .5 FC loss of 0. I performed the overnight test, but got up a little late this morning and the sun was up and shining. The CC stayed at .05 and FC went from 38 to 36.5 which might be because I have stopped adding bleach to get the FC level down. Should I stop the bleach or not?
 
Re: I have gone through the shock process two times this yea

My filter's pressure remains at 30 whether the pool is in use or not
Your gauge is bad and needs replacement.

Even though you are losing very little FC, the rule of thumb for stopping the shock process (lowering your shock level chlorine) is...

1. Pool is crystal clear

2. CC's of .5ppm or less

3. loss of 1.0ppm or less using the OCLT test
 
Re: I have gone through the shock process two times this yea

Hi chknlly,
I had similar problems with my pool a few months ago. I also have a sand filter. I quickly got the green out of the pool but it was cloudy. Unfortunately, it takes a while for the sand filter to get the "cloudy" out of the water. I added a few cups of DE to coat the sand and help filtering and it worked great. You'll have to backwash more often because it's filtering better but it cleaned up the water in just a couple of days instead of a week or more.
With the help of the guys on here, you'll have a clear pool in no time.
It's almost fun going into the pool store now because I typically say "no thanks" when the guys behind the counter tell me I need all the junk they want to sell me.
 
[]CH 80 (person at the pool store said CH only really matter

CH 80 (person at the pool store said CH only really matters if you have a concrete/plaster or whatever kind of pool, not vinyl is that true?)
That is correct but, that's the very first time I've ever heard that a pool store person said it! :shocked:

One big favor you can do for yourself is replace that gauge and order a good test kit if you don't have one.

Once you've replaced the gauge, note the pressure and then backwash if it's over 15 psi. Then note the 'clean' number. Backwash whenever it rises 25% above the clean number.
 
Re: I have gone through the shock process two times this yea

I just replaced my gauge and added DE total 1/2 cups (I am leery of this amount because other posts mention at least one cup being added but mine raised by 2 psi when I added the second 1/4 c.). My FC is at shock level, so I am to only add bleach if if drops below shock level and continue shock level until the pool is clear, correct? BTW I'm using a Taylor test kit.

How soon after I add DE do I backwash? I was thinking tomorrow since I am backwashing daily until it clears. Does that sound okay?
 

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Re: I have gone through the shock process two times this yea

Hey, just a note, but you probably should not have the dolphin in the pool while shocking. It could void your warranty. I have that same one you do, and given how expensive they are, it might not be worth risking it. I know the manual says it should only be in the pool at a maximum chlorine level of 4 ppm. Seems low to me, but then it did come from Leslie's. :)
 
Re: I have gone through the shock process two times this yea

RobbieH said:
Hey, just a note, but you probably should not have the dolphin in the pool while shocking. It could void your warranty. I have that same one you do, and given how expensive they are, it might not be worth risking it. I know the manual says it should only be in the pool at a maximum chlorine level of 4 ppm. Seems low to me, but then it did come from Leslie's. :)

Also, I go pretty much the entire swim season without needing to backwash. You are probably far overdoing it by backwashing twice a week.
 
Re: I have gone through the shock process two times this yea

Only twice? Yer doin' good by my standards!!! Kidding aside, my experience is that my CYA gets too high and the shocking is darned near useless when that happens---takes ages to clear even though your FC is at high numbers. Are you SURE your CYA is only 80? Are you shocking with stabilized chlorine instead of unstabilized by any chance?

My extreme, get-the-water-clear commando move is to drain some water, add fresh, then buy 12% liquid chlorine, and camp by the pool, adding chlorine every hour or two and testing, testing, testing. Pool School explains it way better than I can. The liquid works faster than the granules, it seems.

I've found, through many years of being the "pool boy" is that my own pool does much better at CYA 30-50. Any higher, it gets too hard to shock. Also I try not to let the temp get above 85 F; blooms seem to happen much more quickly in warmer water. Good luck to ya----been there with company coming for the weekend and the pool clouds the day before they arrive.....
 
Re: I have gone through the shock process two times this yea

applgrl said:
Only twice? Yer doin' good by my standards!!! Kidding aside, my experience is that my CYA gets too high and the shocking is darned near useless when that happens---takes ages to clear even though your FC is at high numbers. Are you SURE your CYA is only 80? Are you shocking with stabilized chlorine instead of unstabilized by any chance?

My extreme, get-the-water-clear commando move is to drain some water, add fresh, then buy 12% liquid chlorine, and camp by the pool, adding chlorine every hour or two and testing, testing, testing. Pool School explains it way better than I can. The liquid works faster than the granules, it seems.

I've found, through many years of being the "pool boy" is that my own pool does much better at CYA 30-50. Any higher, it gets too hard to shock. Also I try not to let the temp get above 85 F; blooms seem to happen much more quickly in warmer water. Good luck to ya----been there with company coming for the weekend and the pool clouds the day before they arrive.....

Wow, are you new here? The situation you describe is exactly why we recommend the use of liquid chlorine instead of pucks and powders. Many of our members don't need to shock for years. Maybe you should read through Pool School a bit more...
 
Re: I have gone through the shock process two times this yea

Aw come on, Ohm-y, a sense of humour is a valuable thing when the pool turns green :lol:

However, I don't believe my suggestions were off base. CYA level is a prime consideration at the point when your pool DOES, unfortunately, become "perma-cloudy" and need to be shocked. From Pool School:

"At high CYA levels it may be impractical to use such high FC levels, lower FC levels are often sufficient though they take longer to kill algae. At very high CYA levels, over 80, a partial drain/refill to lower the CYA level is usually required."

This is absolutely my experience! To reiterate what I would do, having been in this situation:
1) evaluate CYA level. Is it accurate? Are you inadvertently adding more by using stabilized granules instead of "shock"?
2) consider a partial drain and refill if you find CYA to be alarmingly high
3) use 12% liquid chlorine as a shock
4) test often
5) let Pool School explain the relationship of CYA to free chlorine (and take care not to let it get too high)

If this is bad advice, do let me know and I will offer my humble apologies to chknelly.
 
Re: I have gone through the shock process two times this yea

I just went thru the CYA situation. I've had my pool for about a year and I always had trouble holding chlorine levels, cloudy water, occasional algae blooms, etc. My CYA was in the 80's and I was always fighting my pool. I finally decided to dump about 20% of the water. Low and behold, everything got much easier and the pool was sparkling in short order.
I'm a relative newby to pools and pool chemistry but from what little experience I have, I'd agree with applgrt. Dump some water. You'll be glad you did and in my case, it wasn't hard at all. I backwashed thru the skimmer until the water got to low for that and I switched to the pool vac line which sits quite a bit lower than the skimmer. I took out about 18 inches of water. It worked to pefection. I then re-filled (about 5 hours with a hose) and all was well. Even helps drop the CH level. My CYA went from 80 or so to about 45, my CH went from 490 to 400. Not bad for a minor drain and fill and the pool is much, MUCH easier to handle now.
My advice (for what it's worth) is to dump enough water to get your CYA in line and start anew.
 
Re: I have gone through the shock process two times this yea

Mesamav said:
I just went thru the CYA situation. I've had my pool for about a year and I always had trouble holding chlorine levels, cloudy water, occasional algae blooms, etc. My CYA was in the 80's and I was always fighting my pool. I finally decided to dump about 20% of the water. Low and behold, everything got much easier and the pool was sparkling in short order.
I'm a relative newby to pools and pool chemistry but from what little experience I have, I'd agree with applgrt. Dump some water. You'll be glad you did and in my case, it wasn't hard at all. I backwashed thru the skimmer until the water got to low for that and I switched to the pool vac line which sits quite a bit lower than the skimmer. I took out about 18 inches of water. It worked to pefection. I then re-filled (about 5 hours with a hose) and all was well. Even helps drop the CH level. My CYA went from 80 or so to about 45, my CH went from 490 to 400. Not bad for a minor drain and fill and the pool is much, MUCH easier to handle now.
My advice (for what it's worth) is to dump enough water to get your CYA in line and start anew.


Sorry for the dumb question...
Where does the cya come from anyway? i thought the pucks were the only way besides the grainular form, did you accidentally put to much or?...
 
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