No, it's not actually sand. It's soil. Much like ADA Aquasoil. You don't want to mix it with sand.
Aquasoil can be purchased from from ADG or AFA (forum sponsors). Shrimp Sand can be found on Amazon.
Actual sand is inert and will do nothing for you other than exist. In a tank so small, it's likely most important to have enough of a high-quality buffering substrate to keep parameters in check.