Help... green pool... here are my numbers...

[DLD]

25psi before and 14 after, and 14 tonight. yes it is running 24/7. the filter is about 28 - 30 inches in diameter. You want us to clean it more often than the weekends?

If i use the more conservative CYA of 50 and a FC target of 20, the calculator suggests adding 4 gallon 2 quarts of 6% bleach.

 

[frogabog]

It changes in the bottom, in the yellow chlorine section. The suggested chlorine minimum/max and shock levels change. At the top, you have to enter in your now value on the left column, then enter the target value in the right column. Then it will calculate.

Make sure your goals are set for Trouble Free Pools (at the bottom of the calculator).

 

[linen]

25psi before and 14 after, and 14 tonight. yes it is running 24/7. the filter is about 28 - 30 inches in diameter. You want us to clean it more often than the weekends?

When shocking, I would clean it whenever it goes up 5 psi from your clean measurement.

If i use the more conservative CYA of 50 and a FC target of 20, the calculator suggests adding 4 gallon 2 quarts of 6% bleach.

That is what I get too. You just won't know when/what to dose next. If you test tomorrow night with your OTO chlorine test and it is below 10, you could re-dose appropriately...but you are still flying kind of blind here since you would like to keep it up at 20.

 

[DLD]

Thanks everyone... will report when i have better numbers.

Dara.

 

[anonapersona]

Remember to brush and use the pool leaf rake to get any debris out of the bottom of the pool.

 

[x2rider]

Thanks, ya I finally figured out that the amount raised is based on pool capacity vs bleach %/volume, and the target FC is what changes.

Until she gets her real test kit, can she dilute the pool water for oto? I guess you would have to test the tap water first. I can't usually tell the difference between the yellow blocks that are side by side anyway, that's why I really like the good test kits.

 

[linen]

Until she gets her real test kit, can she dilute the pool water for oto? I guess you would have to test the tap water first.

She could, distilled water works good for dilution.

I can't usually tell the difference between the yellow blocks that are side by side anyway, that's why I really like the good test kits.

That is my problem too. For me, the OTO is really only good for knowing there is "some" chlorine in the pool.

 

[DLD]

What is OTO? Couldn't i use RO water that we drink? How do you do the dilution method? My test kit is suppose to arrive sunday. The water is clear now, there is some settled dusty green debris settling in the bottom but not much, by tomorrow it will probably be all clear even with the low dosing.

 

[linen]

What is OTO?

OTO is a test for Total Chlorine. It is the test that is typically packaged with a ph test in a combined vial. From pool school:

OTO
Orthotolidine

OTO will only test TC but it is a 'bulletproof' test that will not bleach out and will always tell you if there is chlorine in your pool. It will be different shades of yellow if chlorine is present and will turn orange to reddish or even brown at very high chlorine levels. It's a good test for a daily check to see if there is chlorine in your pool and is the test that is usually found in 2 way chlorine/pH testers.

Couldn't i use RO water that we drink?

RO should work great.

How do you do the dilution method?

Using the OTO test mentioned above (you can usually pick it up at walmart for a few bucks), if you think your FC level is 20 ppm, then you might do a 3:1 ration of RO water to pool water. Once you get your TC reading from the OTO test, multiply it by 4 to get you actual TC (total chlorine). When shocking, you total chlorine will typically be very close to your FC level. As you can see this method can get a bit inaccurate.

My test kit is suppose to arrive sunday. The water is clear now, there is some settled dusty green debris settling in the bottom but not much, by tomorrow it will probably be all clear even with the low dosing.

Keep you FC levels high, then when you get your kit you can immediately do an OCLT (see my sig for the link to the shocking process).

 

[x2rider]

I took my Taylor 2006 kit over today, and DLD has all the numbers wrote down, but 2 tests were a little strange, so maybe someone can explain what's going on.

DLD, can you post the numbers I got.

TC was 10
Ph was 7.8

CYA was 100, pool store measured 85.

I think the first test that was weird was the Total Alkalinity, I put 37 drops in, could it really be 370?
The Calcium Hardness test, I put a ton of drops in, and it never really turned blue, it went clear, then it started having blue "debris" in clear, if that makes sense. It was like it had blue dirt particles swimming in the clear fluid.

 

[linen]

CYA was 100, pool store measured 85.

I would trust your numbers here x2rider. It may very well be much higher. Dilute it in half and do the test again, multiply result times 2.

I think the first test that was weird was the Total Alkalinity, I put 37 drops in, could it really be 370?

Yes, check the fill water, it is probably high.

The Calcium Hardness test, I put a ton of drops in, and it never really turned blue, it went clear, then it started having blue "debris" in clear, if that makes sense. It was like it had blue dirt particles swimming in the clear fluid.

I am not sure on this...anyone else?

 

[DLD]

Ok, the numbers I have with x2riders help are:
FC 10 (was that FC or TC?) I wrote down FC
CYA 100
PH 7.8
TA 370
Calcium Hardness 350

 

[DLD]

Based on those numbers and the calculator, we added 7 182oz jugs of 6% bleach, and 32 oz of 20% muriatic acid.

 

[linen]

How big is your pool and what kind/surface is it? Better yet put your pool and equipment in your sig. With a CYA of 100, or possibly higher than 100, you are going to have a hard time staying at the high FC levels you will need for the shocking process. I recommend that you do a partial drain and refill.

 

[x2rider]

Ya, that was the FC of 10, I typed the wrong thing.

From her first post, the pool is apx 20,000, fiberglass.

 

[linen]

First and for most do the CYA dilution I mentioned previously. Again, you should probably do a drain, but let see how high it is.

Sorry I missed the volume when I scanned this thread again...

To go from FC of 10 to 25 (shock level from poolcalculator) for a CYA of 100 and 20000 gallons should only be 3.4 jugs of 6% 182 ounce jugs. Poolcalulator tells me you went to ~41 ppm FC. Just let it drop for now.

To go from 7.8 to 7.5 pH using 20000 gallons, TA of 340, and 0 ppm borates I get 65 ounces of 31.45% MA. Are you sure you had 20%, that would be unusual, maybe 20 baume? If it was 20% then you should have added 102 ounces of MA.
Confirm which MA concentration you have, check your pH again, and then add the appropriate additional amount.

 

[x2rider]

pool calculator shows shock level of 25 for cya of 100, but the chart shows 39, why is it so far off?
pool-school/chlorine_cya_chart_shock

 

[linen]

good point x2rider...yes that is a bit confusing, when I was posting I was thinking "I should also check the chart...but they can't be that far off can they?". Well at that high of CYA level apparently they can and are Sorry about that

My understanding is in general the chart is more aggressive than the poolcalculator. Both will work, but the chart will get there a bit faster but with a little higher stress on surfaces and equipment. I tend to use and recommend poolcalculator, since it has all the calculations for all of the parameters in one place. Nothing wrong with using the chart though...

Any plans for doing the CYA test with dilution?

 

[DLD]

Update: test kit came in about 10am today!! :-D My test time was 11am - but it took me a while to learn and double test for accuracy - took until 12 noon

(Hubby did add about 3 inches of water this morning before the test kit came - using the old test kit and dilution method the FC showed 45 and hubby was concerned it was too high and added some water.)

11am test results using new TF-100
FC = 44 So for the FC test... after said drops it promptly changes from dark to very faint pink (is that the change i am looking for or do i have to keep adding about a million more drops until it is absolutely perfectly clear when held to a white back ground?
CC < 1.0
TC < 45
TA > 220
CH = 280 to 300
CYA = 65 Really!
PH > 8, maybe 8.2 (yes, we used 31.45% muriatic acid - 20 Baume)

Based on CYA of 65 (which i checked and rechecked and have no doubt of my test method) the chart shows a FC target of 26 (yes I extrapolated). Then plugging all data into the TF calculator :arrow:
I need to let the chlorine drift down or should we dilute?
I need to add 56 oz of muriatic acid. or add 100 oz and aerate to lower the TA. Right??
Need your thoughts.
Thx. Dara.

 

[duraleigh]

Dara,

Don't do anything. Yours is another example of the value of doing your own testing.

Your pH is likely a false high as a result of the FC being really high.

For now, no other adjustments are needed except to let the FC drift further down and then hold it constantly around that 26ppm level.

What does your water look like today?