I’ve taken to using an old cake pan, a desk fan, and a towel. Fill up the pan with water, stick one end of the towel in the water, drape and clip the other end to the fan and let it sit running for a few days. Before the towel gets gross, toss it in the laundry when it’s dry and grab another towel

It works so well I’m completely confused as to how/why there isn’t a commercialized product like that, it completely solves the cleaning/highschool biology experiments problem