This booklet introduces guidelines for teachers at any grade level to set up and maintain a simple aquarium and through it introduce simple biological ideas to their students. Natural and cost-saving aquarium-running strategies are discussed and common, hardy fish and plant choices are described. Many demonstrations and experiments are included on items such as testing water quality, identifying life forms that can be found in the tank, home-making and growing fish food, and encouraging fish breeding. Chapters include: (1) Introduction and Rationale; (2) Getting Started with the Aquarium; (3) Nutrition; (4) Water Quality; (5) Selecting Fish and Plants; (6) Culturing Organisms from the Aquarium; (7) Culturing for the Aquarium; and (8) Fish Diseases and Treatments. Appendices include: resealing leakers; a simple brine shrimp hatcher; the balanced aquarium; common conversation; and a sample worksheet for experiments. (WRM)