Diamond Watchman Goby - Black Spot under his mouth.

[lutz493]

Picked up a Watchman Goby early today, he was hiding under rocks most of today and has recently decided to come out.
He is being very active eating the sand which is pretty cool )
Anways - He has under his mouth a large patch of black it looks almost like a gotee - I am just curious if this is anything bad?
Also he sorta hops up off the sandbed on his tail and takes in a big breath of water..
This normal traits of this type of fish?
Thank you

 

[snakes'n'fish]

Yes that is pretty normal for them. The black spot under the chin is something adult sleepr gobies get. Don't worry he sounds fine. I hope he dont rearrange your tank like mine did .

 

[lutz493]

Thanks alot -
Was just wanting to make sure - He popped out tonight, looked around for a couple minutes, tested the sand in his mouth and then dug himself about 3-4 homes.
Very busy little fish.
Any of my snails who decide to hang on the bottom don't need to worry about getting around - He has no problem picking them up and moving them to new destinations.

 

[spider crab]

Mine has the black spot as well.