Kohler Devonshire 5ft Drop-In Bubble Massage Bath with Heater - K-1357-G "need replacement jet bath tub" Questions

...jet pump wont turn off or sometimes turns on by itself while in the bath, everything seemed to be working fine until I needed to turn off the jets. They turned off but started up again on their own ...

jet tub? I don't want to mess up my tub. I need to know how to get rid of the flakes and bacteria coming out of the air jets. I see this question all over the internet but all answers given are geared