I am making a web app similar to 4chan (for a very specific audience), but due to database storage limitations (currently at most 5 MB), the app needs to delete old posts by anonymous users to prevent the DB from reaching its size limit.
I want to keep a limit on 2000 images at once (images are stored outside of the DB).
Can users get angry if their images get deleted automatically? Should I mention this in a FAQ or in the image posting form?