It’s a vertical tank so no room for water to slosh side to side. Excess tongue weight is far more desireable than a CG behind the axle. Weight distribution hitches and a sway bar add stability but nothing will compensate for a poorly designed trailer or improper loading.
Don’t try to steer your way out of a sway, you’ll only add more energy to the pendulum. Hold the wheel straight and steady and let off the gas. Brake ever so gently if you are going downhill.