Pool want more chlorine than was made this year :)

kirbinster

Well-known member
Apr 30, 2007
293
NJ
I cannot seem to feed my pool enough chlorine. Woke up after a heavy rain last week to find the pool milky white. Chlorine was down to about 1ppm and pH was low. Started adding bleach, about 5 96oz bottles. Pool turned dark green, and pH was even lower. This weekend I have added 20 gallons of bleach, and 3 boxes of 20 mule team Borax, pH is only up to 7.2 and chorine levels reached about 3ppm. I have never had a problem like this and am quite confused. Pool is a 20 x 40 IG vinyl pool. There is no slime or sliperyness, just green. Yesterday the shallow end finally looks clear and the deep end is only light green. Today I added three more gallons bleach. What happened?
 

dmanb2b

TFP Expert
LifeTime Supporter
Apr 4, 2009
3,734
NY
Can you post a full set of #'s? If your CYA has disappeared over the offseason, it could have converted to ammonia, but it could also just be organics?
 

kirbinster

Well-known member
Apr 30, 2007
293
NJ
Well I'm going to have to go out and buy some more reagents to do those tests, but it appears to be getting better finally. Its just strange how it went from crystal clear on Weds to milk white on Fri, and dark green on Sat. Its now clear in the shallow end and slightly green tinted in the deep. I did add 4 pounds of CYA on Saturday, as I have not added any in a year or two and figure between rain dillution and filter backwashing I have lost a bunch.

This is the first time in 10 years I have ever had a problem. You are not going to believe how I normally test my water and determine when to add bleach. Not scientific, but it has worked well -- I use the taste test. Yes I am serious.
 

Bama Rambler

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2009
22,969
SouthWest Alabama
I bet it hasn't worked nearly as well as you think it has.
Seriously, a good test kit is a drop in the bucket compared to the last two items in your sig. Get yourself one and stop guessing!
 

kirbinster

Well-known member
Apr 30, 2007
293
NJ
I have a good test kit, just need to replace the reagents. Not sure what you mean about it not working as well as I think, I have never had an algae problem in ten years. Not sure this is algae either, as it is not slippery at all, but perhaps. I think it was just a huge load of pollen that washed in from the woods behind our house after a huge down pour.

As for the last to items in my sig, it gets worse. I have a very bad case of NAS, and it now includes the following:


Nikon D300, D90, D5000, NIKON GLASS 85mm F/1.8 D, 105mm f/2.8 Micro AF-S VR, 18-200 AF-S VR, 70-300AF-S VR, 70-200VR AF-S VR f/2.8, 10.5mm Fisheye, 24-70 AF-S f/2.8, Sigma 10-20mm HSM, Sigma 30mm f/1.4 HSM, Tamron 200-500mm, 2 SB-600 Speedlights, Manfrotto 190MF3 tripod & 322RC2 ball grip head.
 

waskydiver

LifeTime Supporter
Jul 29, 2009
191
Living in the pacific northwest, I deal with a lot of rain water.

Rain water actually has a very low pH... around 5.7.

However, I usually find that the aeration caused by the rain actually tends to ballence any changes in pH, meaning that during the rainy seasonS, it is the TA that I have to keep an eye on. (Also, rain water has a low TA, and usually dilutes the TA in the pool water).

But, of course, my results are not going to be everyones.

I am thinking that perhaps you had a high TA and CH to begin with, and the drop in pH lowered you CSI to the point where you were you found the pool "milky white".

You then raised the pH with Borax, and gave a shock. The raising the pH could have increased your CSI, clearing the milky white, BUT... if you had copper in your water, the shock could have oxidized the copper, turning your water green.

If it were me, I'd:

-Get a full set of numbers to see if the CSI would support the milky white water.
-Do an overnight chlorine loss to see if you are fighting algae.

If you are not losing chlorine over night, get your water tested for metals.

Based on this information, you may find yourself continuing with your shock, adjusting your TA (and hopefully not your CH "too"), adding a sequesterant.
 

kirbinster

Well-known member
Apr 30, 2007
293
NJ
Interesting theory. Not sure if it applies though as the Borax was not added until day three of the follies. Where would copper come from? It is a vinyl pool with PVC lines and a titanium heat exchanger - no copper in the system to leach out. Also don't think aeration is a factor as the water rain seeps into the pool as the solar cover was inplace so there was no rain directly hitting the water's surface.
 

waskydiver

LifeTime Supporter
Jul 29, 2009
191
Ahhh... the lack of aeration would explain how the acidic rain (relative to your pool water) would drop your pH instead of your TA.

Yea... my theory is a "little" far fetched. Just seeing stuff a little atypical... (I'm used to algae going green to white, not white to green).

Overnight test should answer the question as to if you are fighting algae. If so, you know what to do. If not, I think more tests are in order. Copper can come from all sorts of places, even your source water, and accumulate over time.
 

PaulR

LifeTime Supporter
Jan 11, 2009
1,966
Cupertino, CA
CSI usually works the other way around, high CSI meaning calcium is getting saturated which will lead to precipitated calcium as clouding/scaling, lowering CSI will clear it up.

An overnight FC loss test can do no harm and could point the way out. Or a chlorine-demand bucket test.
--paulr
 

kirbinster

Well-known member
Apr 30, 2007
293
NJ
Today pool is fairly clear in shallow end but still has a green tint in dark end.

Total and Free Chlorine both read 2.0
pH is 7.0
Total Alk is 50.

I just added another 4 pounds borax, 12 pounds baking soda and 1.5 gallons chlorine.
 

kirbinster

Well-known member
Apr 30, 2007
293
NJ
No, not really. I did not add any last year and only used about 20 pucks. So, I figured it was probably low and hence added 4 pounds as the chlorine was vanishing so quickly. It is definitely getting better, but at a decreasing rate of improvement the last day or so.
 

dmanb2b

TFP Expert
LifeTime Supporter
Apr 4, 2009
3,734
NY
FC at 2.0 is pretty low...but again, not sure what your CYA # is? Also interesting FC testing method above...I usually keep our FC in the 6-9ppm range and can't taste it and barely get any chlorine smell.
 

kirbinster

Well-known member
Apr 30, 2007
293
NJ
Just checked pool this morning after making yesterday's additions:

Cl Free 0.75
Cl total 1.5
pH 7.3
Total Alk 100

So, except for chlorine it is looking much better. Added another 3 gallons bleach.

I'm going to take a sample to the "pool store" and have them test it today.
 

esim13

Well-known member
Oct 31, 2009
320
Denham Springs, Louisiana
Please Please test your CYA then post your results like this:
FC
CC
pH
TA
CH
CYA
It makes it soooooo much easier to read and gives everyone all the info they need. Thanks!
 

kirbinster

Well-known member
Apr 30, 2007
293
NJ
So I went to the pool store and had them test the water. They have a fairly sophisticated setup. They have a bunch of square-sided "testtubes" that each have powdered reagents in them for a set test. They use a pipet to inject water into each one and then use a computer controlled colorimeter to directly measure and record the readings into the computer. Any way, here is what they came up with:

FC 3.8
TC 3.8
pH 7.7
TA 90
CU & FE ~0
Stabilizer 10 ah ha!, BUT wait...

How can we believe the stabilizer is only 10? Wasn't it on Saturday that I added four pounds of CYA to my 20x40 IG pool. Doesn't that increase the level by about 30 all by itself? So, now what????
 

frustratedpoolmom

TFP Expert
LifeTime Supporter
In The Industry
May 20, 2007
12,177
SWSuburban Chicago, IL
It can take a week for your CYA to fully dissolve and register. I'm a big skeptic of pool store testing regardless of how elaborate their set up is. If you added enough to reach 30 and you didn't backwash then you should have 30. Give it another few days and test it again and you can always add more later.
 

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