my goldfish died suddenly

Question
Hi Jaymie
        I have a weird question to ask. This morning I feed my two goldfish like I do every morning, when I turned around from their tank I heard a sound like a bang. I turned  back around and one of the goldfish was missing. I found him dead inside a cave I have in the tank for them. My boyfriend said it looked like he had been there for a while, but I know that I saw him swimming when I feed him. The other goldfish in the tank seems fine. Any ideas as to what could have happened.

Answer
Sharon,
If you are sure he was swimming in the tank at feeding time, he might have ran into the glass. If the tank is not big enough, and it's feeding time, they will try to get as much food as they can. Another thought is maybe the two fish crashed into one another. Other than that, I have no idea what could have happened.