ES stream - remove specific stream content for all users

Hi,

I have been searching for the methods to remove specific stream items i.e. Groups - promoted to admin and add to group etc. I found the method in ES>Applications>select app>configuration.

Now that I have turned all these configurations off for the specific application stream items, how can I remove all old similar items from the the stream for all users. In my users, nobody benefits from seeing "promoted to admin" for instance and it would be desirable to remove all previous stream items.

Thoughts?

Thank you in advance for your guidance.

Todd