Thanks for the link, I may have to try those. The reason I ask is that I have a goby/pistol shrimp pair, and they are not aggressive feeders. In fact, I rarely see them. They have their own tank. I tried small ghost shrimp, but those only live a few hours in saltwater. Small guppies don't last very long. I think they may have eaten 2 ghost shrimp in about 10 days. I've tried frozen brine and mysis, but I don't think they're eating them, and I don't want to pollute the tank. There are lots of copepods in the tank, but that seems like small fare for them.