Sound insulation toilet cistern

Hello,
our toilet is located right next to a bedroom. The enclosure (installation wall) has not yet been built. I have received the tip to use a styrofoam board between the toilet cistern and the wall for sound insulation (especially for the noise that occurs when refilling the water after flushing). Are there any opinions on this? Thank you.

Won't help.

What kind of wall will it be? Material and thickness?

What kind of wall will it be? Material and thickness?

11.5 cm Poroton

11,5er Poroton

You can forget about 11.5 Poroton right away. Soundproofing is zero. It's like a straw gate.

11.5 Poroton you can forget about right away. Soundproofing 0. It’s like a straw gate.

It’s already there. The question is whether you insulate in addition to that.