Pool Bleaching?

[surgdog]

I have been using the BBB method for several months and I think the pool looks great with clear water. I will attach a pic.

We just had to get a new pump and the pool guy and my wife think the water is too clear. Their argument is that due to the fact that my gunite pool is blue-green finish that the water should not be as clear and the pool guy gave her the idea that liquid bleach is "bleaching" the color out of the concrete of the pool.

My argument is that if the water is not clear then it is cloudy and not as sanitary. That a Cl level of 4-10 no matter how you get it will not "bleach" the color of the pool.

Am I standing on sound principle here? Can liquid bleach at any level take the color out of the concrete?

On a side note I am thinking about putting in a SWG. Everyone happy with those?

Thanks.

 

[chem geek]

So long as you aren't pouring concentrated bleach or chlorinating liquid in one place quickly and instead are pouring it slowly over a return flow with the pump running, then the pool guy is completely wrong (even pouring in one place wouldn't likely bleach the plaster and if it did it would be local to where you poured). Once bleach or chlorinating liquid or any other source of chlorine is dissolved and circulated, it produces IDENTICAL CHLORINE in the water. As for a Free Chlorine (FC) level of 4-10, I assume you have Cyanuric Acid (CYA) in the pool. If your CYA level is 50 ppm, then the active chlorine (hypochlorous acid) level in the pool is the same as in a pool with 0.07 to 0.2 ppm FC with no CYA. There's no way this would discolor plaster, vinyl, or anything else except delicate molecules like chlorophyll which is why algae turns from green to gray.

If the water were discoloring the plaster, then you should see a line form at water level where the plaster above the water was darker in color than that below the water (assuming one lowers the water level and has the plaster "dried out" equivalently). Even then, it wouldn't necessarily be the chlorine. Do you notice any such water line color difference?

For comparison, my white plaster pool (also at night) has a lighter more aqua appearance. This comes from the red in sunlight getting absorbed by the water far more than the blue so the reflected light looks more blue. Your pics look quite a bit darker and bluer than mine which makes sense given the color of your plaster. How in the world can the water be "too clear"? It's supposed to be clear in terms of being able to see the bottom drain almost as if you can touch it. Any coloring of the plaster will just make it look like it is colored, but won't make it less "clear" -- you should still see objects on the bottom of the pool almost as if you can touch them. The diffraction of light through the water makes the apparent depth (at angles close to vertical, so looking mostly straight down) about 3/4ths of the real depth so a 6 foot depth will look like 4-1/2 feet.

It sounds like perhaps your wife was expecting something much darker blue, but that has to do with the color choice for the plaster and nothing to do with the chlorine. Did the color of the pool change over the past few months? It sounds like it used to be cloudy before BBB, but if there were bleaching going on then the water should look lighter over time.

 

[Guest]

No bleaching, but I would ask what your CH levels are, and your pH. I would suspect scaling or calcium deposits on the plaster.

SWCG are not for everyone, but then again, nothing is for everyone! I don't see getting one again (I've had three different ones), but many here like them and they work well for them. Do not assume that it is a "set it and forget it" though. It will need occasional maintenance/cleaning, and you will need to still pay attention to your FC levels.

 

[surgdog]

Ch levels are greater than 350 and pH is 7.6-7.8.

I just don't think my wife is use to sparkly water. So I decided since BBB works why complicate life with a SWG (also very expensive).

By the way I ordered a Liquidator today from you company Bruce and this is not a commercial but I got confirmation and a tracking number in less than an hour. Great service.

Thanks.

 

[Guest]

I can take no credit for the fast shipping or info, as that is all Sal! He is on that stuff!

I can say thank you though, for both the order and the kind words

Thank you again! Let us know how it works out!

 

[acroy]

I have SWG but if it dies, not sure if I'll replace it. Getting tired of adding acid all the time. I rigged a acid-doser to cut down on the work involved, but we go through a gallon of acid a week in the summer.

The Liquidator is an awfully good, cheap, simple way to get Cl in the pool....

I do love the Salt feel though and will keep salt and borates in the pool for the feel and the sparkle