Lionfish Mouth Extended

I'm late jumping in here, but I actually don't have much to contribute anyway - never seen anything like this before with my lion. I would try going to www.wetwebmedia.com and dropping the WWM crew an email to see what they say...between all of them, someone has likely dealt with this before.
 
Here are the readings for the tank

Amonia - 0
Nitrite - 0
Nitrate - between 0-5

I fed him a krill and he ate it finally, but his mouth is still the same.

Hopefully its just an infection.

I saw him yawn a couple of times, I was hoping it would snap back, but it didnt, but at least he is opening his mouth more than before.
 
Pace,

As I mentioned earlier. resist the temptation to feed him for a couple of days. That yawning that you see is an attempt to straiten things out.
 
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