I have the tank in my salon and am getting the fish today.
It is totally hygenic! You wouldn't be allowed to do it if it wasn't!
The clients feet are washed before the treatment and the tank has a Uv sterilser and a 4 level filtration system which keeps the water clean and kills harmful bacteria constantly.
You replace a couple of buckets of water twice daily and use a special hoover to clean any waste.
Not sure I understand why people would be worried about putting their feet in after someone else as I'm sure most of you go swimming in the sea which is filthy?!
I'll let you know how popular it is and any other info I get today when the guy comes with the fish!
Oh also it has been banned in the States as they were doing it the Asian way where you have multiple people with their feet in one tank, not very hygenic.