New footspa - what's this for?

[MonsteraAddict]

I have a new footspa now the weather is warmer and my feet struggle. What would you put in the little compartment? The instructions call it a 'medicine' box but no futher instructions. I have a nice foot soak... But this little box is intriguing...

Just googled this because I think my footspa has something similar but I've never put anything in it.

This what I found on Amazon on the product description of one similar to the photo you posted:
The medicine box can put herbs to enhance foot bath effect. Or pair your soak with a diffuser using your favorite essential oils, and you’ve just created a memorable spa day at home.

It's not exactly good English and doesn't totally make sense either but it might help!

Maybe if you have bath salts, or those little mini fizzy tablet things?

Is there a foot spa equivalent of a dishwasher tablet that goes in there?