Squeazer

[Squeazer]

Hello all, I got taken by the pool store this season trying to deal with algae as a result of high CYA levels. I drained the pool yesterday and am now filling it with my well water.

The well water has no hardness, no metals, but very high tannin levels.

i have a 15,000 gallon 24 ft round above ground pool. FC 125 cartridge filter, 2speed pump and I am using the Taylor K2006 test kit.

As soon as the pool finishes filling I will post chemical readings, but a quick test just now shows CYA at 80. So draining and refilling seems to have helped, as the reading before was off the charts high.

 

[duraleigh]

Welcome to the forum.

but a quick test just now shows CYA at 80.

How full are you? 50% full means your CYA will be 40....that's good. 98% full means your CYA will be 80 ppm....not good.

Since you have a K2006, please post test results of your well water for CH, pH and TA.....You'll want to know that.

How did you test for tannins?

 

[RonsPlc]

How much water did you drain?
Fresh well water should not have any CYA in it.

 

[Squeazer]

Dave,

I will go test well water now. Tannins were tested with professional water test. My drinking water looks like weak tea in a clear glass, so I know it is an issue and here in this part of south Louisiana it is a known issue as well!

I have about 25% of the pool to fill when I did the CYA test at 80.

Ron,

I drained my pool because of the dichlor I was adding. It was off the charts high, drained approximately 75% of the pool water. I was kinda freaked out about draining any more as I didn't want to mess up the liner. I know I may have to do a partial drain and refill again if the CYA is still too high.

Off to to test well water!

 

[duraleigh]

So, your CYA should end up around 60 ppm. Just a touch high for manual chlorination but very manageable. Use Clorox for FC.

The FC should likewise take care of the tannins....keep FC up around 10 ppm until your pool is crystal clear.

 

[Squeazer]

Ok, well water test

ph: off the charts high. Professional test said ph was 8.4, based on what I saw that makes sense.
TA: 250 when no green color was evident, 270 when sample wouldn't turn more red.
CH: 20

 

[duraleigh]

Go ahead and purchase 2 gallons of 31% muriatic acid. You will need almost all the first one to get pH down around 7.4 and then the other one will be on hand as you will have to lower pH periodically.

Is the water in the pool clear? If not, got a pic?

 

[Squeazer]

Dave,

I haven't put put anything in the pool yet. So the pic in the post is with all the tannins!

Test results

PH 7.8
TA 230
CH 40
CYA 55

I added 162 Oz of 10% bleach, calculator called for 196 Oz, saw somewhere it said add a little less and retest.

Also added 8 Oz dry acid and 8 Oz 31% Muriatic acid.

I will retest in 30 to 40 minutes.

- - - Updated - - -

 

[duraleigh]

What was the result. I do not recall working to remove tannins before so I am very interested in your progress.

 

[MarianParoo]

I am interested too! Btw, with your FC additions, just go ahead and add what PoolMath says. We go slowly with other chemicals, but on chlorine you're fine.

 

[MarianParoo]

I am following your other thread now:
Test results, test results, test results

 

[Squeazer]

Dave,

I truly expected the tannins to clean up much sooner. I finished filling Sunday at about noon and I think it will be Tuesday AM before I have gotten them all out. When they installed th pool I wasn't here, so I don't know if the granules cleaned it up sooner. I will ask and report back.

 

[Caco]

Please keep in mind that my experience with tannins was with aquariums and was a couple of *ahem* decades ago so there may be better options out there
The chlorine should precipitate the tannins in your water so they can be cleared out. I just used to put in a shock level dose, pour the clear water off and then remove the chlorine and it worked well.
You could use a bucket test, ie put some pool water in the bucket and see how much chlorine it takes to precipitate it out in the bucket and then scale up for the pool. At least it may give you an idea of how much longer it may take
I also used a activated charcoal filter with good success, probably not effective in such large amounts needed for a pool though

However if you do run into a problem one of the more chemically experienced people here should be able to help
This article may give some pointers to them (I have to admit I dont understand it) http://www.wwdmag.com/membrane-technology/tannin-removal

Not sure if any of this is any help but I wish you luck