Each dose will contain 3 200mg tabs equaling to 600mg. So the order should look like take 3 tabs po q6h times 3D.
Id say that chocolate milk may have the most potassium of them all. Water does not have any nutritional content (though it is still important). Juice overall will vary, milk does have a high amount of potassium but the added chocolate syrup does add some more.
Https://www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/fitness/art-20048269