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pool2012
07-09-2012, 05:11 PM
I'm caring for a 10k gal. outdoor pool that gets full sun most of the day. Water temp is 81 currently.
We've used pucks and now we have cloudy water. Before I found this forum, I had the water tested at a pool shop. Their recommendation was baking soda and soda ash. So I added the prescribed amount. My water test (done myself) showed high FC and low TC which in pool slang might be considered chlorine lock. I added bleach. Now TC is high as well.

My current test results are FC >5 (the drop test was maxed, with a test strip it was maxed at 10), CC 10 (maxed also), TC (with test strip was 10), pH 7.2 (with both tests), TA 210 with drops (maxed with strip at 180), with a test strip the stabliizer maxed at 150. I think I understand I need to keep the chlorine up at 25ppm until the water clears...along with brushing the sides and daily vacumn.

Question: how do I do that when the tests don't read that high? if the max of the test is 5, I think I dilute the pool sample with 5 units of distilled and sample that - then read the result straight? Sound close?
Thanks.

Watermom
07-09-2012, 05:32 PM
We think that everyone needs a good test kit. The one we recommend is the Taylor K-2006 or 2006C which you can get through the test kit link in my signature below. Try and order it early in the morning while the seller listed is Amato Industries. Sometimes they sell out during the day, but usually restock overnight. Some other sellers don't sell it for as good of a price.

Since the kit is only sold online, you need something to use until you get it. Get a cheap OTO (yellow drops) / phenol test kit, or if available at YOUR Walmart (check availability (http://www.walmart.com/ip/HTH-6-Way-Test-Kit/17043668)), get the HTH 6-way DROPS test kit, which is compatible with the Taylor K2006. Test the pool as soon and you can, and post the results. If you get the 6-way kit, ALSO test the water you FILL the pool with, especially if it's a well, and post THOSE results as well. (The HTH is the best available kit you're likely to find locally, but it's not the K-2006. It can only provide rough measurements chlorine levels above 5 ppm, and it measures "TOTAL" hardness, rather than "CALCIUM" hardness, which is not ideal.)

Until you can get the Taylor K-2006, you can force your kit to read higher with a dilution method described here:
Testing Without a Good Kit (http://poolsolutions.com/gd/how-to-test-your-pool-without-a-good-testkit.html )

You do lose accuracy with dilution, however, so this is not meant to be a permanent way to test. Just a stop gap until you can get the good kit.

Please fill in your pool's information in our pool chart. It makes it easier for us to be able to help you.

Pool Chart Entry Form (https://docs.google.com/spreadsheet/viewform?formkey=dHBLTzdpX19DZVlzUTRLOTU5ZFlZSWc6M Q)
Pool Chart Results (https://docs.google.com/spreadsheet/ccc?key=0Ahjo2iDF0aJgdHBLTzdpX19DZVlzUTRLOTU5ZFlZS Wc)

Repost with the chlorine results you get when you dilute. Also, tell us exactly what all you have added to the pool, meaning ingredients and not just 'shock.'

Hope this helps a little. Welcome to the Pool Forum!

(P.S. No such thing as "chlorine lock.")

UVWater
07-09-2012, 06:08 PM
If the pool was maintained with only pucks for a long time the CYA levels are likely very high. I would expect you'll need to drain some water and add more to try to get the CYA down into an easier to maintain level.

Watermom
07-09-2012, 06:43 PM
it would be best for us to verify what his actual CYA reading is before advising him to drain.

pool2012
07-09-2012, 06:50 PM
I retested with the dilution method and FC looks like 2 to 2.5, CC is the same.
Since July 1st, when we noticed our eyes burning and realized our pH was about zero (but the pool looked crystal clear), we've added approx 18 pounds of baking soda. With no improvement in pH we raced to the pool store, which prescribed more baking soda(14 lbs) and soda ash(1.25 lbs). With this addition the pH was readable, but the TC was off the chart high and the FC was low and the pool was cloudy. Realized we needed another solution to the problem since the pool store wanted to address hardness and we have a fiberglass pool...and hardness level was good. Saw this website and found that we might be low on chlorine since our stabilizer was so high (from our intense use of pucks, usually 4 at a time in a floater). The pucks are out. We added 6 qts of bleach before I decided we better verify before we get to far gone.

pool2012
07-10-2012, 07:43 AM
I just tested this morning with these results: TC 10 CC 10 (both with dilution method), pH 7.6 TA 220 Stabilizer (with the test strip) maxed at 150.
The pool water appears more cloudy than yesterday, but the yellow tint is gone. I've brushed the sides three times yesterday and will vacumn now. It appears the TA has increased overnight. Yesterday I had 210 and today I have 220. Perhaps that is change of 10 is not significant? Since the water is still cloudy I need to increase chlorine until it clears? Thanks!

Watermom
07-10-2012, 08:56 AM
I'm skeptical of that CC reading of 10.

Try your CYA test using the disappearing black dot test instead of strips. You'll have to dilute the sample to get a reading. Take one part pool water and one part distilled water. Mix and then run the test on that. Multiply your result by 2. If you still show a reading of 100 with that, do it again but this time take one part pool water and two parts distilled. Multiply the result by 3. This dilution method won't be super accurate, but will at least get us a better ballpark reading of what your CYA actually is. At any rate -- no more trichlor pucks or dichlor shock powder in your pool!

What is your calcium hardness reading, by the way?

You are right that a 10ppm difference in your TA results is insignificant. But, your alk is to high. Please read the following two guides:

Lowering Alkalinity Step-by-Step (http://poolsolutions.com/gd/lowering-swimming-pool-alkalinity-step-by-step.html)

Using Muriatic Acid Safely (http://www.poolforum.com/pf2/showthread.php?13111-Using-Muriatic-Acid-to-Safely-Lower-Your-Pool-s-pH.html)

Yes, you will have to keep your chlorine high. Please read the Best Guess Chlorine Chart in my signature below. Also, with such a high CYA pool, you are going to have to have the K-2006 kit. The other kits are not going to be able to read the high chlorine levels you are going to have to run. Test kit page in my signature above.

pool2012
07-10-2012, 09:24 AM
TH was 100 at 7:15 this morning.
The FC and the CC were the same color on my test this a.m. I used a 1 pool : 4 distilled water dilution that showed 2.5: which would give me 10.
I don't have a disappearing black dot test. All I have is the 5 test kit and strips...I know I need the more extensive kit but I can't locate it locally and it takes time for delivery.
The pool is now cloudy to the point I can barely make out the vacumn head at the bottom of the 5 foot deep end.
When you advised to keep the chlorine high, I follow the chart according to my stabilizer level of 150...so I should maintain 25ppm and test the level with the dilution method. And I believe I read 2.5 gallons of bleach raises chlorine 5ppm per 10k gal...so in theory (assuming the FC is 10) I would add 7.5 gallons of bleach.
Then I'd add acid to lower the TA. Sound right?

Watermom
07-10-2012, 11:09 AM
1 gallon of 6% bleach will add 6ppm of chlorine. Do NOT add 7.5 gallons to your pool!

Did you order the K-2006 kit yet? It is not sold locally.