Constant daily low free chlorine!!!
- Thread starter mrdorkdar
- Start date
Didnt have a chance to test again same day and didn’t use the spa, but tested it just now and fc was 2.5. Quite a big difference from 9 yesterday morning...
So did you determine that the sanitizer loss was due to insufficient CYA and have you determined an accurate 24 hour decay rate? With no bather load and no ozone you should be less than 20%
Well I did add cya, and the spa is covered in the shade, and we didn’t use it. So it has to be biofilm...
How much?
Near as I can tell, you added 8ppm. Approximately.
Try adding six times that amount over however many days it takes, and then perhaps you can decided if CYA does anything to Chlorine loss rates.
If you determine that you really do have a bioflim problem, note that you're in good company -- I had a brand spanking new hot springs Grande delivered with actively growing biofilms, and, well as you can see if you decided to read my blog post (the link to which I posted earlier), I learned "the hard way" if you will, and boy did I learn about biofilms and ahh-some 
. good luck in your purge experience if you can't solve the decay problem with CYA -- your goal is to purge until you have ahh-some dosed water, filters installed in their normal positions, and the water is completely without visible contaminants. some tips
- keep some ahh-some water in a bucket to wipe surfaces/cover
- dose 10-15ppm FC along with ahh-some
- clean your filters normally, then throw them into the spa vessel while it is still dosed with ahh-some.
- when your filters are clean, set them aside until you get no visible contaminant release. then put them into their normal positions.
. good luck in your purge experience if you can't solve the decay problem with CYA -- your goal is to purge until you have ahh-some dosed water, filters installed in their normal positions, and the water is completely without visible contaminants. some tips- keep some ahh-some water in a bucket to wipe surfaces/cover
- dose 10-15ppm FC along with ahh-some
- clean your filters normally, then throw them into the spa vessel while it is still dosed with ahh-some.
- when your filters are clean, set them aside until you get no visible contaminant release. then put them into their normal positions.
I didn't rule out anything. Bio-films are an ongoing never-ending issue is my position.
It sounds to me like you've ruled out any effect CYA has on spa water above 8ppm.
The original poster is welcome to do as they like.
*edit* I realize that delleno was not responding to me. I misunderstood their comment. I apologize.
yea not to to worry we were just typing over each other, your post appeared while I was re-writing my response to include the possibility that the CYA issue may not in fact be solved!