I tested my hydration level on a machine at a local pharmacy, and it read -.17. is that alarming? my husbands read +.29.

I don't know: I have no idea what a "hyrdation level measuring machine" even is. The best way to judge hydration is urination. You should urinate a few times a day and it should be light yellow. The darker the urine is, and the less often you urinate, the less hydrated you are.

Water: Drink enough water daily so that your urine is mostly colorless. Have a healthy diet, exercise 30 minutes/day, drink plenty of water, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/.