A versatile fluid experimental apparatus with three degrees of freedom is newly designed and built for laboratory experiments of rotating fluid dynamics. To evaluate its performance, we conducted fluid experiments within a triaxial ellipsoid undergoing latitudinal libration over a broad range of amplitudes and frequencies, at a constant rotation rate, using only two low-speed motors. Velocity measurements obtained via ultrasonic Doppler velocimetry suggest that the fluid’s resonance frequency agrees with both theoretical and experimental results from previous studies. Repeated experiments using different transducers further show that the measured frequencies arise from coupling of inertial modes derived via the Gledzer–Ponomarev method. Notably,our systematic study identifies a parameter space in which triadic resonance can be excited,suggesting that it tends to be triggered at or above the resonance frequency of the triaxial ellipsoid. The experiments demonstrate the effectiveness of the apparatus. In the future,more experiments can be conducted on precession,libration,and the combination of both in rotational fluid dynamics,thereby deepening the understanding of rotational fluid dynamics.