I see a lot of Japanese smart toliet seats around with a bidet spray built into them and thinking of getting one. Only question is what is needed to connect them to a water supply. I am imagining a direct connection is not allowed because of the backflow risk from the jet nozzle and I don’t want to go back to having a header tank just for it (especially as they seem to need a minimum 1 bar water pressure. So what do people do in practice? Thanks