They can put the sponge in a mixture of water and a little Clorox, to kill germs and freshen them. Then rinse well.

That's what I do for mops, sponges, and my tub non-slip pad. Also, I put some in the toilet too.

For any green mold or green pollen on concrete or wood outside my house, I put Clorox and water in a bucket and use an old mop to just splash it around.

In minutes all green and mold are gone. Clorox is cheap and not just for the washing machine.

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