I honestly think the answer is a matter of preference. I find this one to be very strong, so I would not use as much as someone else. The instruction on the tube is to use the entire tube. I obviously did not and did not use the entire tube of any of the bath salt tubes I had in one bath. I would minimally get 2 maybe 3 out of what is left. You don't even need to use this in a bath. You could simmer a little in water on the stove or a warmer in a room. Would be great for meditating.