Sloshing is the violent motion of a resonant fluid in a moving tank; when the fluid moves and interacts with the tank, the dynamic pressure from such an interaction can cause large fluid deformations with tank walls. In this study, a 3D numerical simulation of sloshing was carried out with five variations of the tank model, i.e., prismatic, rectangular, tube, spherical, and the new model tank with a filling ratio of 25% and 50%. Forced oscillation motion in a roll used frequencies 1.04 Hz and 1.34 Hz. The amplitude of movement was 8.66°. One pressure sensor was used to measure dynamic pressure in the mid of the tank. Because sloshing deals with large deformation and discontinuities, the particle method was suitable for the application. This study used smoothed particle hydrodynamics based on weakly compressible SPH (WCSPH). SPH is a Lagrangian meshless method known as mesh-free computational fluid dynamics. Open-source SPH solver version 5.0 was used to reproduce sloshing in different tank shapes; in addition, advanced visualization was performed using the VisualSPHysics add-on in Blender version 2.92. The sloshing visualization is more realistic and attractive than conventional SPH post-processing. The results of this study indicate that different tank shapes influence reducing the value of dynamic pressure and hydrodynamic force. It is found that a practical tank shape is a tube tank and a new model tank with a reduced dynamic pressure value of 9% and 11% and a reduced hydrodynamic force value of 36% and 48%.