I've had multiple twin spot, diamond and sleeper gobies. From my experience, all 3 of these seemed to be very difficult to keep healthy over a long period of time in a small tank. They need very mature sand beds to sift. Although I've had couple that took to prepared foods, they did not take it readily from day one. Also with a diamond and sleeper goby, they grow quite large and require larger tanks. In addition, you need a very tight lid on the tank. I've a couple jump through even egg crate.
Andy