I designed this 3 sponge rack using Tinkercad. Each space is ~1" wide to accommodate a range of sponges. The holes are meant to help aid in drying and ventilation.
eSun PLA 1.75
5.35 meters of filament (15.97g)
1 hour, 28 minutes
Rotate STL to print on the front or back face of the holder.
Screenshot from Tinkercad