I just pulled these out of my soil, and I did pull out a similar piece about 2 days ago. I’ve inspected every inch of the tank, the heater, thermometer, etc. (anything glass that could have broken) but it doesn’t seem like anything is shattered. That leads me to think these were already in the soil, especially since they were in the middle of my layout and not near anything glass.

I did find one thread from years ago online that mentioned glass shards in this soil. Apparently it could be quartz, I’m not too sure. Should I be concerned?