D'Addario Planet Waves humidfier replacement sponge

Hi all.

I have a couple of these, and after dampening the sponges a few times, they have started to disintegrate, and there is some black stuff on them. Can I just cut down a regular sponge and use it in the black container?

Thanks in advance.

yes.

It comes with a yellow cellulose sponge, which is the same as the basic ones you get for dishes.
If you want it to last longer, you can use a synthetic sponge, or floral foam