I just say one of those guys at petco, did a quick iphone search, which told me I could keep him in a 75 if he ate brine shrimp. I asked the guy at petco what they are fed, he said brine shrimp and that the gobies ate it fine. So I put him in my tank, pretty cool lokking fish, he found a nice hiding spot, and at feeding time, he saw the shrimp and peeked out, but he didnt eat. Probably jusr his first day in the tank, but I have plenty of copeopods in there JIC the petco guy didnt know what he was talking about (pretty likely). Very nice looking fish though, I wonder if anyone had any experience with them? I will post pics when he is out of hiding.