Clownfish hole in caudal fin

[jimmyx36]

When I first got this clown a month ago it had a white speck on its tail after coming of the QT into my display. It's always healthy but just in the last day or two I noticed that the white speck is now a hole I can see clean through. Is this sign of any kind of disease or just a possible injury/bite?

Thanks!

 

[jimmyx36]

The little white line on the fin was something in the water and isn't a slit in the tail or anything.