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

[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

[KevinD]

Hi Janet,

I measured the chlorine level earlier this evening in my pool using the Taylor kit. The chlorine level measured at 11ppm. I did use the 10mL water sample in order to conserve the reagents - thanks for the recommendation.

I will measure again in the morning and report back.

I am definitely thinking it is not algae and something in the water chemistry, maybe some metals or something else in the water composition that gives a green tint. The pool liner and water is clear, but there is a green tint to the water when you look at it through natural lighting. It is definitely not green on the pool lining, it is the effect is light passing through the water that makes it have the light greenish tint as you look into the depth of the water. It is still sparkling clear, just with a green tint as light passes through the water. It was not this way on day 1 after setting up and filling the pool.

Kevin

[KevinD]

Hi Janet,

Per your request, I measured the chlorine level again this morning. It measured at 10ppm (20 drops in the 10mL sample). Please note that I have not added any new bleach into the pool water since shocking it on Sunday night.

Kevin

[Watermom]

I don't think it is algae. Doing the overnight test pretty much confirmed that. Looks like you have some metal in there. Kind of odd with city water. I've asked Ben or Marie (our metals guru) to take a look at your thread.

[mbar]

When you drain or lower your water level is there a change in the color of the liner or bucket? If not, then the color is in the water. Do you have copper pipes? It seems to me that the water is tinted when it comes out of your spigots, the slight greenish tint sounds like it may have some copper in it. You can find out if there is copper in your township water. If the water is tinted, I don't think it will be a problem. Do you know if anyone else in your area has the same problem? This is a tricky one since it is the same color in the bucket with your fill water. Please post and let me know,

Marie

[PoolDoc]

I have seen green water from organically chelated iron -- that is, iron that was eroded from old iron or steel pipes by bacterial growth. These chelants (sideraphores) are apparently much stronger than anything you can buy commercially, and chlorine stable as well.

Your city is certainly old enough to have areas that will experience this problem, but you'd have to call your water company. You could also ask, in the same call, if they are adding anything to the water that would give it a greenish tint.

If you would, add another dose of bleach to both buckets. I'd assumed that the dose given was enough to break any chelant, but now I'm not so sure. I can't find anything on the oxidative destruction of sideraphores, and I don't understand the chemistry well enough to have any sort of educated intuition about it.

In the pool where I experienced this most notably, it would take up to 3 weeks for the greenish color of chelated iron to disappear.

[KevinD]

Hi,

I just checked both buckets again after the second 24 hour period (total 48 hour so far). Listed below are is the info for each sample - no changes in status of water color, clarity and sediment, still the same:

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 also measured the chlorine levels in both buckets, too. Interestingly (to me at least) was the chlorine levels in the hose water is higher than that from the pool sample. The pool water sample measured 22ppm CL while the hose water measured 28ppm CL. Both samples has 1/2 cup of bleach added to them 48 hours ago, but the pool water has previously been shocked, too (so it was starting with an already high CL level). Does this make sense? The pool water also has additional pH and CYA modifications which had not been done to the hose water.

Is it still worth me adding another does of 1/2 cup bleach to each bucket per Ben's recommendation? I imagine this would put the CL levels ridiculously high (will use up most of my reagent to measure CL levels ;-) ).

Ben - please let me know if think I should still add another 1/2 cup bleach to each bucket.

Marie - the water pipes in my house are copper. For reference, my house was built in the early 60's.

As long as the greenish water is "safe" for my kids, which I assume is the case, I am fine with it. It is still very clear, just has a greenish tint to it. If there was a way to clear this up, I am open to it, but I do not want to have to do something too drastic if the water is fine with the slight greenish tint. Doe the Taylor kit have the ability to measure for copper or iron in water? I have not read through the guide that came with it, so I am not sure of all of the tests available in this kit.

I will also try to call my town hall to see if they have any information about the green tint to the water. If I learn anything, I will report back. Last week I just received our town's annual report on water quality, the values tested and provided in the report are lead, barium, mono-chloramine, fluoride, nitrate, nitrite, perchlorate, total trihalomethanes and haloacetic acids-5. Are any of these helpful?

Thanks again for all of your help.

Kevin