A ceramic vortex finder (CVF) is the central pipe (gas outlet) of a gas cyclone, which is an important structural component within gas cyclone separation. Its main application is within high temperature processes, within the energy and cement industry where the atmosphere is highly abrasive and corrosive. The CVF has the purpose of inducing well-defined flow field resulting in optimal performance of the cyclone.  Ceramics and refractories are superior when it comes to high temperature stability, resistance against chemical attacks along with abrasion resistance. The aim for a longer lifetime of the CVF creates an importance of further investigation into factors influencing the strength of the material. Fracture toughness is an important parameter to focus on in the CVF application. This is because it’s known that fracture is the major cause of failure for brittle materials. This creates an interest into further investigation of the parameters influencing the casting process including water addition and porosity.  This project work aimed to investigate the impact of water addition on the CVF material. The focus was on identifying how much the casting process influenced the fracture toughness. The results showed that 4.5% water addition is the best amount to use for the CVF application. This water amount gave the minimum porosity with the highest fracture toughness. The water amount ensured a good flowability of the castable along with a curing time above 50 minutes, making it possible to cast in the production.