Baby tarantulas eat crickets, or pieces of crickets, that are approximately the same size as the spider, minus the legs. Baby roaches, maggots and termites can be used as food for a baby tarantula. Prey of an appropriate size offered to a baby tarantula twice a week is normally sufficient.
Very young baby crickets generally receive the water that they need from the prey insect's body. Once a baby tarantula's body grows to approximately the size of a bottle cap, it should be given fresh water in a water dish that is easy to access. A bottle cap can suffice as a water dish until the spider grows a bit larger.