Eyeglass "test"?

[Wes45]

My pool is in balance and I noticed my eyeglasses had a film on them after I got out of the pool. So I happened to be cleaning the garage and found some Natural Chemistry Pool First Aid from the days before going BBB. I broadcast 1/2L on the surface and the next day my glasses were pretty much film free when I got out of the pool.

Is there something in the BBB method I am missing or is the Pool Aid something that can be used to keep the film from developing on my glasses? I'm thinking if the film is on my glasses then the water is not as clean and clean as it should be.

My glasses stayed film free for 2-3 weeks so I used the rest of the bottle today.

 

[chem geek]

Most likely the film is from the remnants of suntan lotion or other oils that are on the surface of the pool water. Because oil and water do not mix (without surfactants such as soap), the oil tends to stay on the surface of the water so it doesn't get broken down from chlorine very quickly (the chlorine level at the surface is very low due to breakdown from sunlight). Also, saturated oils don't get affected by chlorine much at all. Usually, these eventually make their way to the filter assuming you've got enough flow rate in the skimmer.

The use of enzymes will help to break down such chemicals that chlorine has a harder time to break down. There's nothing wrong with using such a product. It costs more, but it does actual work allowing dissolved oxygen to oxidize additional chemicals faster or more completely than chlorine can do. It's not necessary, but if one wants to reduce surface films and doesn't want to try other techniques such as longer pump run times at faster flow rates, it's certainly reasonable to use if you're willing to pay the price. Note that many of these enzyme products also contain surfactants so they don't actually break down some chemicals but instead "dissolve" them into the water (as micelles).

In our own pool, my wife uses a lot of suntan lotion and swims every day. I used to shock the pool when I saw a film, but then decided to give up because the film was getting added faster than I could easily get rid of it and it was only noticeable when first opening the cover and around her when she got into the pool. I know from cleaning my oversized cartridge filter once a year that most of that lotion ends up getting caught in the filter. I don't know how well sand or DE filters would capture such oils -- it's not from physical filtration so much as adhesion so the filter material is important. Do you find that when you clean your cartridge filter it has gummy oil-like substances that look like concentrated suntan lotion (usually tan in color)?

Richard

 

[Wes45]

Thanks, we don't use much suntan oil so it's probably other oils falling out of the air from folks using lawn mowers and weed wackers. I clean my filters 3-4 times a year and they never have any kind of gummy substance on them. So it's probably an affordable solution to use this a couple of times a year when we are swimming. Appreciate the reply.