The invention relates to a bowl system for continuous testing of fluids, especially in the context of industrial processes, preferably by near infrared spectroscopy. The inventive system comprises a bowl (19) placed in a mounting rack (2) presenting a sample basin (22) with an inlet (23) and an outlet (24), a track of rays being directed to said sample basin. In order to facilitate testing, the invention is so designed that said mounting is placed in a housing fitted with an inlet connection (8) and an outlet connection (7) which run across the housing, and that ducts which can be quickly disconnected are provided between the housing inlet and outlet connections, on the one hand, and the sample basin inlet and outlet, on the other hand.