The next time I stayed in a hotel with one ( a two week vacation ) I put some bleach in the Jacuzzi and let it run and figured it was clean. I realize I am a bit on the OCD side when it comes to cleaning, I filled it up again and put some detergent in the Jacuzzi. It almost made me sick to see all the "gunk" that came out and floated on the suds. I had to put fresh water in the Jacuzzi and let it run and repeat about 6 times before I got clean water only. I would figure that in all the time the hotel had been in operation with the Jacuzzi in the room it had never been cleaned, only whipped down.
When I say Jacuzzi, I mean it was a shower/tub/Jacuzzi all in one deal.
So, I'm posting this as a warning if you stay at a place with one and you use it. I'm sure after the bleach it was sanitized. But TO ME, germ free dirt and scum is still dirt and scum. YMMV.
Also, if you have one of these combo units in your home, how do you keep it clean? I realize that some people don't freak out about their own dirt/mess as much as they would someone else's dirt/mess.
I'm sure running the detergent through the unit like I did is probably not a great idea, but there must be a way to clean it.