Scooter blenny got a hole in its head

[Stelioshah]

I have had this dragonet for around 2 years already. Today, when I went to feed the tank I saw that it had a hole in its head which looks like a bite mark. I do not have any crabs apart from 2 hermits. The hole is between its eyes and I am pretty sure that I can see bone... Is this just damage or something more serious?:

 

[vetteguy53081]

I have had this dragonet for around 2 years already. Today, when I went to feed the tank I saw that it had a hole in its head which looks like a bite mark. I do not have any crabs apart from 2 hermits. The hole is between its eyes and I am pretty sure that I can see bone... Is this just damage or something more serious?:

Pic blurry but may have resulted from injury or bacterial issue
Revisit water quality and please furnish clearer pictures

 

[Stelioshah]

Sorry for the blurry pics but this fish just hates me, whenever I get close it runs away. Despite that, even with clear shots I still can't capture a lot of detail... Here are some more pictures:

 

[Jay Hemdal]

It does look like an injury with a secondary bacterial infection - but even the second picture isn't really clear.

Other there other fish in the tank?
Is the dragonet still eating?

Jay

 

[Stelioshah]

It does look like an injury with a secondary bacterial infection - but even the second picture isn't really clear.

Other there other fish in the tank?
Is the dragonet still eating?

Jay

The dragonet is as active as any day, it still eats like a pig and steals the food out of my corals.. I was out of town for a few days so I am uncertain when this happened. Is there anything I can do to reduce the risk of a severe infection?

 

[Jay Hemdal]

The dragonet is as active as any day, it still eats like a pig and steals the food out of my corals.. I was out of town for a few days so I am uncertain when this happened. Is there anything I can do to reduce the risk of a severe infection?

The location is bad - any infection at all is going to be very near the brain.
The general treatment for this would be a broad spectrum antibiotic effective against gram negative bacteria in a treatment tank. Neoplex or Kanaplex are two possible choices. Just avoid “tonics”, they just don’t do much.
Jay

 

[Stelioshah]

Unfortunately its condition suddenly turned for the worse during this past week. I am going to attempt to treat it.. Its right eye seems a bit swollen (the eye membrane is not in the appropriate place). It is heavy breathing, barely moves. It tries to eat but it can't.