When I do my service I let the client soak in the tub with lemons, limes, and oranges. I cut the slices in half. I have a piped system and do not run it while the fruit is in there. If you have a non-piped tub or foot bath the fruit should not get broken up as much. Before I start the rest of the service I scoop them out and discard them. I barely see any ring or residue after I have done the rest of the service that has a soak involved.
What little bit there is I wipe clean when I am finished. I wash it with soap and then I run the tub to disinfect it. Unless you put a huge amount of lemons in and they get beat up, they should not leave that much residue. Test it first before you have a client and see how much is left behind. If it will be a hassle to clean try lemon essential oils instead of the actual fruit so you could get the same effect.
— Karen New is the owner of Spa Touch in Orlando.