The warpaint clown goby might be okay in the pico, but my LFS
tells me that you cannot put two clown gobys together unless they are a mated pair, and two different colored ones can't be a mated pair. It is also very hard to pair them up since it's hard to tell the sex.
I haven't done any personal research on this but my LFS
specializes in only SW
and is owned by one guy who has only one other employee, both are very knowledgeable in SW
. (just to state that it's a reliable source haha)
You should start a thread about it maybe.