I have a Two spot goby who i have to say is one of my favorite fish. He digs little caves under my rock for is "den" and sleeps there at night. More recently he made a den under my brain coral and reburried his old cave...he moved lol.
Durring the day he picks up mouthfulls of
sand and filters it out through his gills, but mostly gets food from the frozen brine shrimp that i soak in garlic.
Pretty sure they dont get more than 3" long which should be fine for a 10 gallon.
All around entertaining fish. Heres a link to em for some read up.
http://liveaquaria.com/product/prod_...216&pcatid=216