Low sanitizer levels will allow nasties to proliferate rapidly in a hot tub causing a myriad of unwanted side effects including increased biofilms.
Biofilms accumulate in all spas & jetted tubs no matter how well maintained & must be removed periodically or a high sanitizer demand will occur along with the issues you mention.
It sounds like Starting fresh with an Ahhsome purge is in order since you have never done one & are experiencing issues.
After which you can follow this guide for chlorine
If you have a question about any information within this Sticky, please start a new thread for yourself where you will receive very quick responses to your specific questions. Thank you! Introduction There are two main things to consider when maintaining your hot tub water, Water Balance and...
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Or this guide for bromine
Originally Posted by waterbear There is a lot of misinformation on the proper way to use Bromine so I hope this primer is helpful. First, you need to establish a bromide reserve in the water. Bromine tablets can do it by themselves but it can take literally weeks until enough dissolves. Some...
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Generally, if starting out with a clean, freshly purged tub, & adequate fc levels
FC/CYA Levels or bromine levels according to bather load & standby demand are
always maintained then there shouldn’t be any scum ring unless there’s an event where someone got in with alot of lotion/sunscreen on, alot of hair conditioner or fabric softener at which point a little extra sanitizer to oxidize it & extra filter cleaning will usually take care of it .
Kudos on getting a kit, update your signature with that & your spa info.
The strips aren’t worth the paper they’re printed on & they will falsely lead you astray with their “ranges”.