Fig. 5) History of the tank. Left column, from top, age of tank: a) 0.6, b) 1.2, and c) 2.5 years. Right column from top: d) 3.0, e) 4.1, and f) 5.1 years. The different colors are a result of using different cameras, the lighting has remained constant. All the prominent organisms shown in the last 2 years appear as frags in the first photo.