1,500 full color photos in one single volume! Easy-to-read instructions make working with this book a pleasure. All AQUALOG -reference books introduce each fish (incl. breeding forms etc.)with at least one color photo and a short description. The ingenious code number system labels every known or newly discovered fish with an individual code number. This number re mains, despite any scientific renaming. Moreover, it enables you to communicate internationally about any fish without the danger of confusion regarding local names!