By Heiko Bleher New 4th Neon Tetra Heiko was able to discover a new neon tetra (Paracheirodon species) in September 2006 and went back in November 2007 to find this jewel again. This is the 4th part about his adventures 40-year-long search and summarizes the discoveries of the former three species (Paracheirodon innesi, Paracheirodon [...]