Small bump on clown gobies head

[Grozzly]

Hey guys,

just noticed this morning my clown goby has a small bump on his head, apologies for the poor pictures.

the LFS does quarantine fish and I have had him now for six months, I did just add two clownfish from that same LFS and they are from a good breeder, they seem healthy.
Any ideas

 

[Jay Hemdal]

Tough to get good photos, I know. It is probably just an injury, perhaps from one of the new clownfish. As long as it is still feeding and acting o.k., I wouldn't try to treat for anything.

Jay