Apologies if this has been asked and answered; I searched and couldn’t find anything similar.

I was cleaning my cat’s drinking fountain and found these small sharp-ish crystal-like things in the water (sorry for the photo quality, it was hard to document). She’s had the fountain for two years and this is the first time this has happened.

Obviously very concerned that she’s been consuming these, and I’m monitoring my cat’s behavior for anything abnormal as a sign of pain. So far nothing.

Does anyone know what these could be? There’s no shattered class nearby, so my best guess is something from the filter leaking out?