Hi! hope everyone is having a great summer. I would like to know if someone has some insight as to what can cause chlorine levels to drop so fast within hours. Here is the scenario. This past Saturday, at 10 am my FC was 5.5 ppm. My 2 kids (4 and 8), my wife and I started using the pool around 2pm and stop around 6 pm. Pool water was around 85 degrees and the air temperature around 85-90 degrees. When I tested the water this morning it was 2ppm. I am puzzle, as I did not think FC could be decrease so fast, especially when my salt chlorinator is working properly and ran as per schedule from 8pm to 5 AM. There was no storm/rain that night or anything I can think could cause such a significant decrease on my FC level. Any advice would be appreciated. Thanks.
My chlorine level drop from 5.5 ppm to 2ppm within 12 hours?????
- Thread starter RESISTENCIA13
- Start date
Hi,
FC drops because of 2 reasons.
1. UV from the sun
2. Organics (including people) in the water like algae, grass, bugs, whatever...
To be sure its not algae, do an overnight chlorine loss test. If there is 1 or less ppm drop in chlorine, then its not algae.
FC drops because of 2 reasons.
1. UV from the sun
2. Organics (including people) in the water like algae, grass, bugs, whatever...
To be sure its not algae, do an overnight chlorine loss test. If there is 1 or less ppm drop in chlorine, then its not algae.
Don't forget potty breaks! If those aren't happening out of the pool then that is using up some chlorine. It is a good idea to up the chlorine level a couple of ppm before and after a big day of swimming. It is safe to swim with FC above minimum and up to shock level for your CYA. FC below minimum level is not properly sanitized.
My CYA level is 80. What do you mean by "sunscreen"?
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My kids take potty breaks outside the pool....I have a "urine detector" warning sign posted and my kids think the water will turn red if they do it in the water.
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My kids take potty breaks outside the pool....I have a "urine detector" warning sign posted and my kids think the water will turn red if they do it in the water.
CYA is the thing that help protect Chlorine from Sun burnoff. (Hence Chlorine Sunscreen)
Just making sure you had some in there. In fact you hav a LOT in there.
If 80 is an accurate reading ( I hope it is not):
Your Target FC for that level of CYA is 10 with a minumum of 6.
That would indicate you are not maintaining sufficient FC to prevent Algae.
Just making sure you had some in there. In fact you hav a LOT in there.
If 80 is an accurate reading ( I hope it is not):
Your Target FC for that level of CYA is 10 with a minumum of 6.
That would indicate you are not maintaining sufficient FC to prevent Algae.
Res, with a SWG it's perfectly fine and recommended to keep your CYA between 60-80 so yours is right in range. I keep mine at 80 as well and target my FC around 8 since my pool has absolutely no shade from 8;00 AM - 6:00 PM in the blazing Charleston sun. After you post your OCLT results, we'll see what next steps might be.
Thanks for the replies and advice. I slamed my pool and then tested. The chlorine levels did not drop more than 1ppm. FC level are ok since. So all, I can think is that some animal went for a swim in my pool that night. I lived in an area wood lots of woods behind my yard. T