Silverfish

Our silverfish clean bathroom grout.
We keep them in a little matchbox,
put the matchbox on the shower floor,
open it up a crack, and turn out the lights.
In the dark they scurry for the mold
and residue of soap, which they digest
as easily as binding glue. The next day,
with the light, they return to their box,
and you just need to move that box
to a dry place. If you don’t let them feed
every few days, then drop one of our
food pellets into the matchbox.