The effects of solution chemistry including pH and calcium contents on permeate flux in a hybrid ozonation-ceramic ultrafiltration (UF) membrane treating aquatic model NOM were investigated. Without ozonation, the permeate flux was observed to be lower at lower pH values. This difference was considerably more pronounced in the absence of calcium in a model NOM solution. Due to electrostatic attraction between NOM and ceramic membrane surface, adsorption of NOM to the membrane was found to be more favorable at lower pH. Significant decrease in permeate flux after addition of calcium is attributed to calcium-NOM complex formation. This effect was enhanced by increasing pH because of increased availability of carboxylic group in NOM. Under continuous ozonation without calcium content, the permeate flux was found to experience almost no decline. At highest pH tested (= 8), the repulsive interaction between ozonated NOM and ceramic membrane surface became stronger due to the increased negative charges of both - membrane surface and NOM. Ozonation of NOM increases the extent of calcium-NOM complexation, making NOM less negatively charged with respect to the calcium complex of non-ozonated NOM. Continuous ozonation initiated recovery of the permeate flux after rapid decline of it during early filtration stage. This result shows that NOM deposited on the membrane is degraded in the process of continuous ozonation at catalytic membrane surface.