Dicholor to shock pool ?

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used the second bag of dicholor tonight....will probably buy some stabilizer --I would think thats a better route. The highest my
CYA could be now is 20 (2 bags of shock) so I will probably just get some stabilizer. Do I need to worry about alkalinity right now ?
 
You may as well continue with the dichlor, just a bit more tonight or tomorrow and you are at CYA 30 where you switch to bleach for chlorine needs.

You are at a calculated CYA of 20 you say. So now, per Pool Calculator, you want to shock at 11 ppm FC (regular shock) and stay below 14 ppm FC (mustard algae shock). You calculated that one lb of dichor adds 6.4 ppm FC and 5.8 ppm CYA. So retest FC and add the volume you need to get from current FC to maybe 12 and note what that added to the calculated CYA.

Mix it well, either with a good brushing or circulation and retest in an hour to see if you got to your target FC. It may well drop a few points as it works on anything in the pool so you may be able to add the remaining calculated amount tonight and start on bleach tomorrow.

After something less than 2 lbs of dichlor you will be at 30 ppm CYA and then you stop using dichlor until you are ready to increase CYA some more. I'll guess you add most of that tonight and the rest in the AM.

Sounds like tomorrow you will be switching to bleach. Then you start a proper shock procedure. Kind of one day delayed due to using the dichlor to raise CYA instead of stabilizer but since you are not really up and running with the electrical that is probably OK. As you read in Pool School, now you will try to keep FC above 13 at all times, but not higher than mustard algae shock levels of 19.

As for alkalinity, no, don't worry about that unless it is very low, like below 60. Low TA makes pH unstable but high TA just makes pH rise over time. High TA is the last thing you deal with, it will slowly take care of itself as you tend to pH. Test pH often enough to catch it when it gets to 7.8 and adjust it down to 7.3 or 7.4. Do measure your TA every week or month because as it changes it affects the amount of acid you need to adjust pH.

Do adjust pH while FC is below 10 ppm. At FC above 10 the pH test in not valid and it is not good to try to adjust when you can't trust that number.
 
OK thanks. Yesterday I tested my FC (this was after putting in 10 oz of shock the night before) and it seemed to be zero(using the simple color test that came with the TF100). I added another 16 oz of shock last night and will retest today.
The pool store said my TA was 0 but who knows if thats accurate.
I will test myself---unless I shouldnt worry about it or is everything else so low I wouldnt get a valid test on total alkalinity anyway ?
PH is holding at around 7.2

I *could just get stabikizer at this point to raise CYA as I dont have any more shock.
Can I just add the stabilizer and then shortly after add bleach ? Can they be done right after the other ?
 
First, forget what the pool store says. You have a better test kit than they do. Use it and believe it. What did your testing say? You need it to be at least 60 ppm. You must know TA before you start adjusting pH, but again use your test values, not the pool store.

Please do a full test of your pool water using the TF100 and post all the results.

Let's see, you were at 20 CYA you said, then added another 16 oz dichlor. What is your pool volume? Adding that to your signature would be helpful. Going by what you said your calculated CYA should be 25 now but please review that.

You will need stabilizer and you will have some choices of how to add it. Stabilizer is found by itself and also in 3" tablets of trichlor and the powdered trichlor you were using. I suggest that you get some stabilizer by itself. I like the HTH brand Stabilizer and Conditioner but it can be hard to find at Walmart this late in the season. Also try places like Lowes, Target, or Ace Hardware.

You may also want some 3" tablets of trichlor to use in a floater at some point. I consider those tablets a luxury and I reserve them for vacation use. Using trichlor tablets can be a lot like the dichlor, you have to pay attention to all the combined effects of them. Stabilizer by itself is simpler. Pool stores will always have stabilizer by itself but some brands are harder to dissolve.

In my opinion, if you are at 25 ppm CYA you are close enough to 30 to get on with shocking the pool. That means adding bleach as often as possible to keep FC up above the shock level for your CYA, but below mustard algae shock level. At CYA 25 that is between 12 and 17 ppm. You will want to get up early, test the pool, add bleach, mix well or circulate an hour, retest hourly if possible and bring the FC back up to above 12. Record the data as you do it so you can predict how long you can wait before the next test.

If you cannot trust the electrical to leave the pool running while you are away, I suggest you get a Wall Whale brush attachment and a pole long enough to reach across your pool. You can really mix the pool well with that thing and it makes brushing the pool so easy.

How long until power is on?
 
According to the pool calculator I am at about 10,400 gallons.
I have been running the pool filter for 4-6 hours a day(only when I am home and awake--usually after work during the week).
The dedicated electric arrives friday.
I am ASSUMING my CYA is at around 12-15 based on adding 26oz of Dicholor. Ive been told here that I cant really measure CYA accurately for at least a week so I have to ASSUME its there.
I will look for the stabilizer. Can I add stabilizer then add bleach right after ? (doing this in front of the return of course with filter running)...
 
You want to put the stabilizer in a sock or knee-hi stocking and tie it off at a return so the water hits it. The flow of water will dissolve the stabilizer. And it helps to squish it frequently.

BTW, with 10400 gallons I get 9.4 ppm CYA as a calculated CYA from 26 oz dichlor. So, from there, you need 30 oz stabilizer by volume .

You can start with bleach now based on CYA 10, and 24 hours after you raise the CYA to 30 you will shock based on that level.
 
gdog2004 said:
ok so if my pool is at 9.4 CYA how high do I raise my FC ? The chlorine/cya chart starts at 20 CYA...not 10 :/
Click to expand...
Shock level for zero to 20 CYA is 10FC. You can confirm this using the PoolCalculator.com

Also use the PoolCalculator.Com to figure your doses for you.
also --I run my pump at 1/2 hp because it leaks a lot when I jack it up to 1 hp(only small drip leak at 1/2 hp). Is it ok to add chemicals at 1/2 hp ?
Click to expand...
Just pour bleach slowly in front of a return. If you are concerned, you can also brush the pool around that area to make sure it mixes in well.

Can I add stabilizer then add bleach right after ? (doing this in front of the return of course with filter running)...
Click to expand...
Yes.
 

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thanks for answering that. I did a quick test last night before adding chlorine. (the PH/FC test in the blue box)
FC was at 5, and PH was at 6.8.
I put in enough bleach to jack it up to 10 to shock. (per the pool calculator)
It is possible that my chlorine may have gone a little higher as my water line is only about an inch above the skimmer.
I assume if my FC is at 11 or 12 its not a big deal.
I will add CYA (which I bought 8 lbs of yesterday in powder form) tonight to try to raise it to 25.
I know you guys mentioned putting it in a sock. How do you get that to stay in front of the return jet ?
Do you mean an actual sock ? wouldnt I need Shaquille O neal feet to hold that much CYA in a sock ? :)
 
gdog2004 said:
thanks for answering that. I did a quick test last night before adding chlorine. (the PH/FC test in the blue box)
FC was at 5, and PH was at 6.8.
I put in enough bleach to jack it up to 10 to shock. (per the pool calculator)
It is possible that my chlorine may have gone a little higher as my water line is only about an inch above the skimmer.
I assume if my FC is at 11 or 12 its not a big deal.
I will add CYA (which I bought 8 lbs of yesterday in powder form) tonight to try to raise it to 25.
I know you guys mentioned putting it in a sock. How do you get that to stay in front of the return jet ?
Do you mean an actual sock ? wouldnt I need Shaquille O neal feet to hold that much CYA in a sock ? :)
Click to expand...

pH of 6.8 is the minimum the test can read, it could be lower than that. What is your TA? Be sure that your TA is 60 or more. This is important. Low pH can damage things.

FC at 11 or 12 is fine, up to mustard algae level is OK which is 12.

Raise the CYA to 30 ppm. 25 was OK, 30 is better, no higher than that for now.

Yes a sock, like a tube sock or a knee-hi stocking. They stretch. I got about 2 lbs in a knee-hi last time I did it.
 
A CYA test of 9.4 must be from test strips and I would put no faith in it. The CYA test that you can trust is a turbidity test and has an accuracy of plus or minus 15.

Trying to move your CYA by 5 points will be problematic.
 
Dave, that is the calculated CYA value from the dichlor used so far. They have not bothered to test for CYA as it has not been in the pool long enough to show up. All new water so calculated values should be good.
 
anonapersona said:
gdog2004 said:
thanks for answering that. I did a quick test last night before adding chlorine. (the PH/FC test in the blue box)
FC was at 5, and PH was at 6.8.
I put in enough bleach to jack it up to 10 to shock. (per the pool calculator)
It is possible that my chlorine may have gone a little higher as my water line is only about an inch above the skimmer.
I assume if my FC is at 11 or 12 its not a big deal.
I will add CYA (which I bought 8 lbs of yesterday in powder form) tonight to try to raise it to 25.
I know you guys mentioned putting it in a sock. How do you get that to stay in front of the return jet ?
Do you mean an actual sock ? wouldnt I need Shaquille O neal feet to hold that much CYA in a sock ? :)
Click to expand...

pH of 6.8 is the minimum the test can read, it could be lower than that. What is your TA? Be sure that your TA is 60 or more. This is important. Low pH can damage things.

FC at 11 or 12 is fine, up to mustard algae level is OK which is 12.

Raise the CYA to 30 ppm. 25 was OK, 30 is better, no higher than that for now.

Yes a sock, like a tube sock or a knee-hi stocking. They stretch. I got about 2 lbs in a knee-hi last time I did it.
Click to expand...


The PH was matched to the lowest color on the chart. I assume there is another test for PH in the TF100 ?
I will do what the calculator says to raise it. What do you mean "damage things" ?
Ok on the sock. But how do you get it to sit in front of the return ? Do you tie it in between the return and the wall or something ?
 
Use two socks if you have to. Tie the sock off at the top with a rubber band and just hang it over the side of the pool in front of the return. Or hang it off the ladder. Then come by frequently (hourly) and squish the sock till all the solid CYA is gone. I'd consider it in the pool when the sock is empty but the standard here is to assume it's in there 24 hours after you add it. Being that much of it will be active in the pool before the sock is totally empty is why I would use the CYA level added before 24 hours has passed from empty sock time.

The TF100 has an OTO color block for the pH test, it and most others do not test below 6.8 but if the color is yellower than the 6.8 reading it does mean that it's lower than 6.8. How much? Unknown till you raise it a little and test. Aim for an amount to go from 6.8 to 7.2 and then re-test about half hour later (pumps running). If it's still low, use the calculator and raise it again.
 
You said that the pool store told you TA was 0, that is a problem. You need to fix that before you worry about pH or CYA or FC.

Please do a full test of your pool water using the TF100 and post the results. Omit CYA test.

Getting TA up to at least 60 is really important, your pH is unstable otherwise. When pH crashes, and you have no idea how low it may be. Everything below 6.8 looks the same, it could be way lower, especially if your TA is actually 0.

It is bad for the equipment. I don't know how long it takes to do damage. Just a couple of days ago you tested pH at 7.2 you said. Point is, tend to this before anything else.

You want baking soda to adjust TA. You will need the big bags that Walmart usually has in the pool section. Or Sams Club, or maybe some other places. If you are at work now you ought to pick some up on your way home. Use the Pool Calculator to see how much you will need to get to 60 ppm, and buy some extra.

Fix the TA before you do anything about pH.

Then when the TA is adjusted to 60, circulate a half hour and brush the pool, then re-test to be certain. Then retest pH, it may have changed.

Then, as Frogabog said, add what you need to raise ph to 7.2, then circulate to mix well and retest in half an hour. Re do as needed to get to 7.2. Do this before you add the CYA into the pool, the CYA has acid and
 
anonapersona said:
You said that the pool store told you TA was 0, that is a problem. You need to fix that before you worry about pH or CYA or FC.

Please do a full test of your pool water using the TF100 and post the results. Omit CYA test.

Getting TA up to at least 60 is really important, your pH is unstable otherwise. When pH crashes, and you have no idea how low it may be. Everything below 6.8 looks the same, it could be way lower, especially if your TA is actually 0.

It is bad for the equipment. I don't know how long it takes to do damage. Just a couple of days ago you tested pH at 7.2 you said. Point is, tend to this before anything else.

You want baking soda to adjust TA. You will need the big bags that Walmart usually has in the pool section. Or Sams Club, or maybe some other places. If you are at work now you ought to pick some up on your way home. Use the Pool Calculator to see how much you will need to get to 60 ppm, and buy some extra.

Fix the TA before you do anything about pH.

Then when the TA is adjusted to 60, circulate a half hour and brush the pool, then re-test to be certain. Then retest pH, it may have changed.

Then, as Frogabog said, add what you need to raise ph to 7.2, then circulate to mix well and retest in half an hour. Re do as needed to get to 7.2. Do this before you add the CYA into the pool, the CYA has acid and
Click to expand...


Hi guys. OK once again the pool store is FOS !
I tested my TA with the TF-100...at about 4 drops it was light purple and 5 drops reddish-pink--6 drops was darker reddish/pink. So I am assuming my TA is between 50 and 60.
Should I add the CYA now then ?
 
What is the current pH?

CYA can be added any time but just make sure TA and pH are where you want them to be because when you go back to shock level you won't be able to accurately test pH. 7.2 is what you're aiming for before you raise it to shock level. You may want to adjust the TA up a tad so it's a good solid 60, if not 70 regardless to help stabilize pH. Tiny bits at a time, then test TA. You don't have far to go so be careful.
 
gdog2004 said:
Hi guys. OK once again the pool store is FOS !
I tested my TA with the TF-100...at about 4 drops it was light purple and 5 drops reddish-pink--6 drops was darker reddish/pink. So I am assuming my TA is between 50 and 60.
Should I add the CYA now then ?
Click to expand...

Right, now remember that about the pool store.

You are done with the TA test when the last drop does not change the color. I wonder if the 7th drop might have changed it some more, but go on and assume 60. That is bare minimum for TA. You may proceed with the adjusting of the pH, or you could bump the TA up just a bit if you choose.

Then, when you are ready, re-test pH and adjust it. There are a few different chemicals that you can use to raise pH. I've always fought against high pH and so I am not really familiar with which is best.

Power will be installed tomorrow? You want to get TA up to ~70, pH to 7.2 - 7.3, and CYA to 30, in that order. Have bleach on hand for tomorrow.
 

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