whatcanido

Hello, I been having my tank for a while now.. and i wanted to know if this crack that I have going on in my tank will cause issues. It’s in my AIO tank and it’s on the last chamber where the return water pump is at. I have added pictures to see what everyone thinks :)

I was looking at my tank today, and noticed something strange. It was what I've now identified as a vermitide snail (its picture below) However, I was scraping off the calcified tube from the bottom of the frag plug of my australian green tip bubble hammer (wall) and I accidentally dropped him...