If you are starting a cold (or temperate water) aquarium then this the book for you. Most people will think cold water=gold fish=easy and they will be wrong. Basics of aquarium (water chemistry, fish biology) plus two possible aquarium designs and the most common cold water aquarium fish available are included in this book. Really all you need if you are a beginner (or if you want to refresh your memory) is in there. The author, Nick Fletcher is a former PFK editor, now specialized in Koi and he knows his stuff inside out. In short, if you want to start a GF aquarium (not a criminal bowl) buy this book, read it from start to finish and you will be ready.... you might even want to keep other types of cold water fish.