The brix meter or Refractometer is a must if you are serious about getting optimum nutrition out of your soil, the Brix measures the long chain sugars or polysaccharides and also gives a good indication the mineral & microbe content of the soil which translates into healthy fruit or vegetable. Ideal measurement for vegetables is 12% + and fruit should be at least 20% +, what we are finding now is that most of us are eating very sick deficient food even though it looks good, even most organic food is low in nutrition, levels are anywhere from 1% to 4%, hence the increase of degenerative disease. Researchers way back in the 1950 found that when they measured food their clients were eating at low brix levels they contracted the usual diseases but when the brix readings of their food was high the food was actually used as a medicine and clients were overcoming their diseases much quicker than usual.
When you grow your food you need to know the nutrition content, a Brix meter will be well worth the investment.