In this study, sediment formation in a ship fuel tank fuelled with a blend of 30% palm biodiesel (B30) was evaluated. The main objective was to understand sediment formation during fuel storage over different storage periods, which has not been previously reported. In this study, B30 was evaluated for cleanliness, water content, contaminants, and other properties before it was stored in a ship fuel tank for 30 days. Regular sampling was conducted every two days during this storage period to monitor and analyse sediment formation. After a storage period of 30 days, B30 exhibited density comparable to its initial condition, with a difference of less than 0.1%. However, its viscosity showed an increase of 1.2%. In contrast, no significant difference was observed in fuel cleanliness based on ISO 4406 and in the measured water content. The amount of sediment formed was consistent up to the 19th day, but from the 20th to the 30th day, it rapidly increased logarithmically, with a 312% mass increase by the 30th day. Additionally, morphological and FTIR analyses showed that the sediment consisted of agglomerated asphaltene and saturated fatty acids. This study reveals that quality control and specific treatments are required in B30 to suppress the formation of sediments.