You want this stuff called ahh-some. We use it to do the deep cleans on the Airbnb hot tubs and jacuzzi bath tubs. (We deep clean them quarterly. Hot tubs get drained, sanitized, and refilled, and the filters get pressure washed in between guests. No I’m not kidding, and yes it is time consuming and uses a LOT of water. Do YOU want to soak in someone else’s skin cells and God knows what else? Neither would I.) Anyway, ahh-some is not cheap but it is extremely effective, and it’s concentrated so you don’t have to use a lot of it. You can get it on Amazon.

For the bath tubs, in between guests, this is how the housekeepers do it, two dishwasher tabs - they use Finish, you don’t want to cheap out on the dishwasher tabs - and several glugs of bleach. Depends on the size of the tub, but it works out to 2-4 cups of bleach. The hottest water, fill it up to the top of the jets. Run for 20 minutes, then let it soak for 20 minutes, scrub inside the jets (our housekeepers use car tie brushes for this) then run jets for 10 minutes, drain, wipe/spray down/scrub if you need to (any junk that comes out usually rises to the top and wipes right off), refill with hot water and run for 10 minutes to rinse. If it’s particularly bad, do a round with a few squirts of blue Dawn - just a little, it WILL bubble - then a rinse round with bleach, and let the bleach rinse round dry on its own and then try running it with just hot water to check the cleanliness.

We purchased a couple of properties with jetted tubs already installed, and as the motors die, we’ve been replacing them with soaker tubs. Way easier to clean.

Caveat: this is what we do with our properties. I PROMISE that this is not typical cleaning for most places, and jetted tubs are likely gross on the inside. We have worked hard and pay extra for our housekeepers to clean these tubs this way every time. If you’re staying at a place with a jetted tub and you want to use it, bring a couple of dishwasher tabs and bleach and clean it this way before using it.