Intek 15' x 48" - water is clear, but pool liner now looks greenish instead of blue

[Watermom]

They can swim. Chlorine at 15ppm with a CYA of 50 won't hurt people, but it may fade swimwear so have them wear an old suit. Take a minute and read the Best Guess Chlorine Chart in my signature below.

Report back in the morning with your overnight chlorine loss and also how your water looks.

[KevinD]

Hi Watermom,

I have definitely shocked the pool - I added ~ 4 qts of bleach last night and now my chlorine levels are above 15 (I diluted my pool water with 1 part pool water, 2 parts distilled water and it measures at least 5, maybe a little darker. Multiplying by 3 gives > 15). I also noticed that pH sky-rocketed as well. It is now > 8.2 (previously was steady at 7.5). Does the excessive bleach/chlorine of the chock treatment also increase pH levels?

One additional fact I forgot about is that I added 12oz of hth "metal control" after filling my pool with water (before adding any other chemicals). I had read online that this should be the first step in the water treatment process. Could this be the cause/source of the light greenish tint to my water?

After further review of my pool & water, I realize the the light greenish tint is in the water, not on the liner. NOTE: It is still present after the shock treatment. If I change the angle at which I look through the water, the "blue/green line" I see along the side of my pool "changes its location." It must have something to do with the pool water chemistry that is causing the light greenish tint to my water (still very clear). Could it be caused by the "metal control" that I added??? If so, is there a way to reverse the effect, i.e. drain some water and add new water? If so, how much should be drained? Or is this something I just need to accept for this season?

I look forward to your response. Hopefully my Taylor kit arrives soon so that I can get more accurate measurements.

One last question/concern - do I need to be proactive to reduce my elevated pH level? Should I take action to lower it or will it lower on its own as the chlorine level drops?

Thank you in advance for all of your support.

Kevin

[Watermom]

Don't trust your pH reading taken while the pool had high chlorine. it will typically read falsely high. Wait until the chlorine drops below 5ppm and then recheck pH.

Why did you add the metal control initially. Do you think you have metals in the fill water? Why don't you do a bucket test to check for metals.

When testing for metals, you'll need the following:

(2) white 5 gallon buckets.
A 1 gallon or 1/2 gallon clean milk jug or orange juice container (to measure with) OR
A household scale accurate to within 1 lb.
A *fresh* jug (96 oz or 1 gallon) of plain 6% household bleach.
A box of 20 Mule Team borax.
An OTO testkit, like the Taylor 1000 or the HTH 6-way drops kit. (Test kit info page)
Lids or towels you can use to cover the buckets.
A plastic or stainless steel tablespoon measure
A plastic or stainless steel 1/4 cup measure
A clean household long-handled stainless or plastic cooking spoon.

To carry out the test:

Use the gallon or half gallon measure to collect pool water.
Fill the first white bucket with 4 gallons of POOL water.
(Measure by adding 4 measured gallons OR by adding 33 lbs of water to the buckets)
Fill the second white bucket with 4 gallons of FILL water, from whatever source is used to fill the pool.
To each bucket, add 1/2 cup of bleach & mix (~80 gal bleach /10K gal pool -- 480 ppm)
Mix completely with the spoon
Wait 15 minutes, and note any color change.
To each bucket, add 1/2 cup of borax,
Mix with the spoon till dissolved completely
Cover with lid or towel.
After 24 hours, inspect. Note clarity, color and sediment, if any visible
After 24 *more* hours, inspect. Note clarity, color and sediment, if any visible
Test both buckets for chlorine levels with OTO. You should not get a 'normal' reading, but report resultant color.
Report results.
Recover the buckets, and wait 3 days, and check again.

[KevinD]

Thank you for the instructions. I need to go to store later today to pick up some of these required items and will start the test tomorrow. I will report back once I start getting results to report.

Kevin

[KevinD]

Hi Watermom,

I started the test process tonight. After adding/mixing the 1/2 cup of bleach to both test buckets and waiting 15 minutes, the water color in the white 5-gallon buckets of both the hose water (used to fill pool) and the actual pool water both have a similar slight green tint to them. There were no green colored items in the nearby area where I am conducting the tests to give the green tint to the water. Please note that both water samples seemed to have a slight green tint even before adding the bleach, however, i could not tell if the greenish tint got stronger or not after adding the bleach. It is a very faint tint, so it is difficult to compare/contrast.

I will report back again tomorrow night after 24 hours. I just added the 1/3 cup of Borax to each and mixed it in. It was difficult to get it to completely dissolve in the hose water because it was cold.

Kevin

[KevinD]

Hi Watermom,

I just checked both buckets after the first 24 hour period. Listed below are is the info for each sample:

Pool Water:
clarity = clear
color = very light green tint
sediment = noticed 4-5 very small black specs, size of sand grain (not sure if these are new)

Hose/Source Water:
clarity = clear
color = very light green tint
sediment = noticed 4-5 very small black specs, size of sand grain (not sure if these are new) as well as one larger black clump, maybe size of pencil eraser. I do not remember seeing this before...

I will report back again tomorrow night. Do you want Chlorine levels tonight? Please note that I just received my Taylor test kit in the mail today, so I now have a more accurate test kit.

Kevin

[aylad]

If you'll go ahead and measure your chlorine this evening after the sun is off the pool, and measure it again in the morning before the sun hits the pool, we can rule out or confirm algae or something else consuming your chlorine, by comparing the two readings. If you'll use the 10 mL sample instead of the 25 mL sample, and multiply your drops x 0.5, you'll make your reagents last longer.

Janet