Clown goby with bump on belly

[baronen]

So I got a clown goby last week as my first fish and it hasn't really eaten well/at all. he is very shy and hides out in a little cave all day. he is also quite skinny. yesterday I got some live brine shrimp and I saw him eat two or three and I stopped watching. today his belly is oddly swollen. it does not have a natural "full" appearance, it looks like he ate a pebble. I will try to get a pic of it but is this what a really full yet skinny goby looks like?

 

I will try to get a pic but he is so shy he darts back in anytime I get close

[baronen]

Pic. he finally moved to a different spot. It doesn't look good, notice the bulky blue mass on his underside

[Humblefish]

Not to be gross, but is the mass coming out of his anus? It could be a rectal prolapse (pics below). If so, there's not much you can do except wait & see if it works itself out.

 

[baronen]

that does look pretty similar. The goby was hiding all day and when I fed the tank he went after one piece and then spit it out. I didnt get a good look. Surprised he is still alive tbh 

[Humblefish]

58 minutes ago, baronen said:

that does look pretty similar. The goby was hiding all day and when I fed the tank he went after one piece and then spit it out. I didnt get a good look. Surprised he is still alive tbh 

Its a long shot, but dosing Epsom salt (1 tablespoon per 5 gallons) might help serve as a laxative. Epsom salt is just magnesium sulfate, so reef safe. Just be sure the Epsom salt is plain and doesn't contain any scents.