Potion of sinking

Potion of sinking. This potion tastes of the most pure and clean water you have ever tasted. It feels cleaning in a way only something this simple and pure could. Any part of you in water ways more than triple its normal weight. You sink 15ft of movement in water every turn contested by a Strength or athletics save DC13. The DC must be beaten to get out of the water. The potion lasts 1 day.