oddly, no. my water is dead neutral with a pinch of salt.
the Gobys are from franksaquarium who gets them as fresh.
I'm just as surprised as you are, and no it's not a mosquito,
an no other fish I have has any similar vertical striping.
I suppose it's possible a Goby was preggo when I got her,
but I kinda doubt it since they were much smaller then,
and I got these fish more than 3 Months ago.
now I'm going nuts eyeballing the main community tank
looking for more babies. I just wish I knew what egg sign
look out for, since my tank already has Ramshorn eggs.
I highly recommend these gobys for nano
tanks or community tanks with <1" small fish,
like that 30gal full of nano stuff in my sig.
they do require live black or tubifex worms
or live brine shrimp every week or two.
I drop the worms into my lava rocks to
give them a chance to hunt them down
before all other fish can get the worms.
gobys will hover like a helicopter to find
and eat live brine shrimp one after another.
here's a close-up of one of my shy adults.