It is shown that in an anisotropic harmonic trap that rotates with the properly chosen rotation rate, the force of gravity leads to a resonant behavior. Full analysis of the dynamics in an anisotropic, rotating trap in 3D is presented and several regions of stability are identied. On resonance, the oscillation amplitude grows linearly with time and all particles are expelled from the trap. The positions of the resonances depend only on the characteristic frequencies of the rotating trap and on the direction of the angular velocity of rotation.