Refilled tub but still high chlorine usage

stakd

New member
Mar 31, 2025
3
Ohio
I recently purged my tub (using AquaDoc instead of the highly recommended Ahh-Some to clean the jets) and refilled. I got the chemistry balanced and the water is pretty clear, but I am having issues with chlorine loss of about 1 ppm per hour. There's also a bit of film on the top that I just noticed today, which I imagine is some biofilm that didn't get purged by the jet cleaner. So I started to SLAM it about 24 hours ago, but I am wondering if I should instead do repeat Ahh-some (which I just bought) purge/drains instead, as I'm not sure if the SLAM would take care of the biofilm.

Here are my numbers:
TA: 60
CH: 130
pH: 7.8

Any help here would be greatly appreciated. Thank you!
 
I'd purge.

Some good info in these posts...

 
Last edited:
I recently purged my tub (using AquaDoc instead of the highly recommended Ahh-Some to clean the jets) and refilled. I got the chemistry balanced and the water is pretty clear, but I am having issues with chlorine loss of about 1 ppm per hour. There's also a bit of film on the top that I just noticed today, which I imagine is some biofilm that didn't get purged by the jet cleaner. So I started to SLAM it about 24 hours ago, but I am wondering if I should instead do repeat Ahh-some (which I just bought) purge/drains instead, as I'm not sure if the SLAM would take care of the biofilm.

Here are my numbers:
TA: 60
CH: 130
pH: 7.8

Any help here would be greatly appreciated. Thank you!
You’de also need to post the FC and CYA level when done.
 
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As I did my tests, I was getting FC loss all over the place (from -2 over 12 hours to -6 over 12 hours back to -1.5 over 12 hours). Is that normal when there is a biofilm issue? Testing with Taylor kit. The tub was closed except for 30 minutes after adding chlorine, the filter was run the same # of hours day vs. night, and I tested FC before adding and 30-60 minutes after the to figure out the loss. Every time I got the -2 or -1.5 reading, I thought I had this problem nipped, but then a high loss reading would happen the next time. .

I got my Ahh-some delivered yesterday (gallon jug) and today I did a couple purges. There was a lot of yellow particulates in the foam (but nothing green) and by the third purge it was white foam. Doing the drain/clean/refill, then will balance TA to the numbers in my first post and report on the FC values/loss issue resolution.
 
The yellow stuff was the biofilm.
Be sure to wipe it away as you go or it can harden on the spa shell.