For the first, curator Fabian Herder has used the River Sieg as a model. “It is a jewel and ideal to use as a model for other rivers in our country,” he explained. The aquariums show the various habitats from the source to the mouth of the river. Each fish needs specific conditions relating to speed of current, water depth and vegetation and Herder had tried to cater for each of the 60 or so species.

On the other side of the lower ground floor are a variety of species from a south-east Asian tropical river. Here there are also various habitats with their own inhabitants – there is even a small waterfall in one paludarium, which also has space for snakes, frogs and tortoises. Willi Miesen, who helped set up the exhibition, estimates there are around 600 animals and says the first fish have already reproduced: “Clearly they are at home here.”

For Herder, the exhibition is a dream come true. “Up to now I have presided over 100,000 mounted fish but we were lacking live animals. Luckily that has now changed.” Professor Wolfgang Wägele, director of the museum, is also pleased with the development and proud of the interactive terminals, which allow visitors to get information about the animals and their habitats.

The Museum Koenig is open from Tuesday to Sunday from 10am to 6pm, and Wednesdays to 9pm. The museum is closed on Mondays, unless it is a public holiday. Entry costs euro 5 (euro 2.50 reduced rate). For more information go to www.zfmk.de (Original text: Thomas Kölsch. Translated by Kate Carey).