Charts & Diagrams A picture is worth a thousand words. That is why we created these easy-to-reference charts and diagrams. Discover ideal water parameters and learn how popular aquarium equipment works. Aquarium Calculators Planning a new aquarium has never been easier. Use our handy calculators to determine how much sand and water you'll need, how to setup a calcium reactor, how much to dose and more. Featured Tanks Occasionally we'll highlight one lucky customer's tank as our "Featured Tank." In addition to bragging rights, we hook up the tank's owner with free goodies. Check out their specs and see what they're doing right.