Chris From Central California

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jblizzle said:
23 drops of R-0871 is only 11.5ppm of FC. That is no where near the correct shock value for a CYA of ~100ppm.

According to the Pool School chart, your shock FC level is ~39ppm ... that would be 78 drops!!! Which is why we generally recommend getting the TF-100 which has a lot more R-0871 ... and even suggesting the XL option which includes even more powder and reagent ... if you are having to perform the shock process.

Try the CYA test with 50/50 mix of pool water and tap water, then double the test reading. If you still have the current mix in the bottle, dump out half and refill with tap water and then double the test result (this should work for CYA levels that are not too high ... like 200+)
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I stopped at 23 because I know it would be around 70-80 drops the way it was going and I would run out. I will try the suggestion of the CYA test.
 
UnderWaterVanya said:
What size sample did you use? The default with the 2006 is 25ml which means each drop is only 0.2ppm vs 0.5ppm with the 10ml sample.

You can use a 5ml sample where each drop is 1ppm but that is not normally recommended - accuracy suffers. With a limited amount of r871 you might want to do that until the water clears and then switch to the 10ml sample to test OCLT and CC's.

Sent via Tapatalk...
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Yes, I did the larger sample, but I will do the other as well............
 
jblizzle said:
Safest bet is to just read the ingredients on the package. Look for something that looks like dichlor.
For example:
The Chlor Brite would say something like: Sodium Dichloro-s-Triazinetrione Dihydrate 98+%
The Power Powder would say: Calcium Hypochlorite and somewhere between 50-70%
There are also sometimes powders made of Trichloro (same as tablets)

Walmart carries HTH products, whose "Chlorinating Granules" appear to be cal-hypo and their "shock N Swim" is also cal-hypo, so I am not sure if they sell dichlor or not.

Any reason you are appear opposed to getting HTH Stabilizer and just using liquid chlorine?
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I mussed the last question, sorry. I never used it is why I opposed, but I will check it out. I am draining the pool again. I can't get CYA below 100.
 
Granules are the solid form of CYA.
You could also use the liquid form of CYA, but it seems to be quite a bit more expensive ... so we recommend the granules.

Posted from my Droid with Tapatalk ... sorry if my response is short ;)
 
jblizzle said:
Granules are the solid form of CYA.
You could also use the liquid form of CYA, but it seems to be quite a bit more expensive ... so we recommend the granules.

Posted from my Droid with Tapatalk ... sorry if my response is short ;)
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I think I will go with the Dichlor, so 27,500 gallon pool about 13 bags of one pounders should be good, right?
 
13 lbs will give you ~29ppm CYA rise. It will also raise the FC by ~31ppm and lower the pH by 1.2

You certainly should not add it all at once.

Remind me, what is your current CYA and what is your target? You are not in the shock process correct?
 
jblizzle said:
13 lbs will give you ~29ppm CYA rise. It will also raise the FC by ~31ppm and lower the pH by 1.2

You certainly should not add it all at once.

Remind me, what is your current CYA and what is your target? You are not in the shock process correct?
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I did a partial drain a few weeks ago and could not get the CYA below 100. (I must have been at over 300 CYA.) The wifey and I decided to go with a full drain and just start over. I got confused with the solid CYA and decided to use the advise with Pools School recommendation pool-school/temporary_pool_guide because the pool calculator said I would need 3 things of this stuff http://www.walmart.com/ip/HTH-Stabilize ... r/17043638 and I am scared.

I was going to use the recommendation of almost 3 lbs of Dichlor a day for 4 days to get me up to around 30 CYA. Am I on the right track?
 

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You will just need to keep an eye on the FC level and make sure it does not get too high for your estimated CYA level. 3 lbs per day will add ~7ppm of FC, but it is highly unlikely that you will loose that much in a day ... you may just need to add 3 lbs every 2-4 days.

Also will need to watch the pH and TA from getting too low. What is your tap water TA and pH?

Do you have a way to aerate to raise the pH (water fall, spa, etc)? without affecting the TA?
 
jblizzle said:
You will just need to keep an eye on the FC level and make sure it does not get too high for your estimated CYA level. 3 lbs per day will add ~7ppm of FC, but it is highly unlikely that you will loose that much in a day ... you may just need to add 3 lbs every 2-4 days.

Also will need to watch the pH and TA from getting too low. What is your tap water TA and pH?

Do you have a way to aerate to raise the pH (water fall, spa, etc)? without affecting the TA?
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Yes TA & pH. No water fall. I do have a spa. I can do the 2-4 days if you recommend it.
 
You just need to test for when the FC level drops so that you can add more dichlor. You do not want the FC to get above the shock level for the amount of CYA that has been added to the pool and is active.

The shock level for a 30ppm CYA (your target after you have added the 13 lbs) is only a FC of 12ppm. If you add it all at once (or too often) your FC could easily get well above that FC level.

What is your water temperature? If it is cool, under 60, then algae will not be able to quickly grow, so there is not too much of a hurry to get everything into the pool.

You may be able to get away with only adding 1 bag every day to start and after a few days make sure that the FC has not climbed too much. If the FC stays above 2ppm and below say 10ppm, then you are fine.
 
jblizzle said:
You just need to test for when the FC level drops so that you can add more dichlor. You do not want the FC to get above the shock level for the amount of CYA that has been added to the pool and is active.

The shock level for a 30ppm CYA (your target after you have added the 13 lbs) is only a FC of 12ppm. If you add it all at once (or too often) your FC could easily get well above that FC level.

What is your water temperature? If it is cool, under 60, then algae will not be able to quickly grow, so there is not too much of a hurry to get everything into the pool.

You may be able to get away with only adding 1 bag every day to start and after a few days make sure that the FC has not climbed too much. If the FC stays above 2ppm and below say 10ppm, then you are fine.
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That's the question I seem to not be able to get an answer to. What happens if your FC is too high? Is there such a bad thing? Yes water is in the 50's.
 
Less of a big deal with a concrete pool I think. The high FC would damage liners (fading).

But, if your throw it all in ignoring the higher FC, your pH is going to plummet and the acidic water could certainly damage the pool surface and equipment.
 
jblizzle said:
Less of a big deal with a concrete pool I think. The high FC would damage liners (fading).

But, if your throw it all in ignoring the higher FC, your pH is going to plummet and the acidic water could certainly damage the pool surface and equipment.
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Thanks! My FC was 30 for around 2-3 weeks, but then again my CYA was over 100. That is why we are draining. I will go with your advise of a pound a day for 2 weeks.
 
MonsterPoolMan said:
jblizzle said:
Less of a big deal with a concrete pool I think. The high FC would damage liners (fading).

But, if your throw it all in ignoring the higher FC, your pH is going to plummet and the acidic water could certainly damage the pool surface and equipment.
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Thanks! My FC was 30 for around 2-3 weeks, but then again my CYA was over 100. That is why we are draining. I will go with your advise of a pound a day for 2 weeks.
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Really the advice is... MEASURE FC so you don't exceed shock levels. Using this method you need to know the theoretical CYA level for each day, making sure you don't exceed the shock level for the CYA you have already added up to that point, plus what you are about to add.
 
MonsterPoolMan said:
jblizzle said:
Less of a big deal with a concrete pool I think. The high FC would damage liners (fading).

But, if your throw it all in ignoring the higher FC, your pH is going to plummet and the acidic water could certainly damage the pool surface and equipment.
Click to expand...


Thanks! My FC was 30 for around 2-3 weeks, but then again my CYA was over 100. That is why we are draining. I will go with your advise of a pound a day for 2 weeks.
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Right, but the shock level for a CYA of 100ppm is a FC of 39ppm ... so you were below that. 30ppm of FC with 0 CYA is a VERY different story as far as the actual active chlorine level.

As UWV said, you need to be measuring the chlorine and tracking how much CYA you are adding. Simply: keep the FC between 2 and 10 ppm throughout the process (on the lower end to start) and you should be fine.
 
So each pound of dichlor should raise my CYA around 2 ppm if I calculated right. I may need 14 lbs when all said and done. I will test CYA every 3 days or so. Water is 3/4 empty right now. We are expecting rain Wednesday thru Sunday, so I would like to get so "free" water this week!
 
I would not waste the CYA reagent until you are a week after your last dose of dichlor (since the test will not read anything below 20ppm anyway).

Just trust the pool calculator to be close enough for CYA and add dichlor to keep the FC over 2ppm (under 10 ppm).

Each 16 oz pack should add ~2.4 ppm FC and ~2.2 ppm of CYA.
 

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