Update:
So this past week I submersed myself into the world of Brix. I deviled in this back in 03', and for some reason, forgot how important brix is for everything from plant health, to helping figure out a plethora of other things. Brix measures the sugars in the sap of your plant. For growing purposes, it runs on a scale from 1 to 32. One being horrible, and 32 being unattainable. The benefits from high brix are to numerous to list. I use it to gauge the plants response to things I'm doing. A heathy mj plant will have a brix of 7 to 9. Over 9 is great, and 12and over is phenomenal. A brix over 12 gives the plant a natural resistencia to pest, molds, and diseases. The little sap sucking bugs that we deal with growing mj do not have a digestive system complex enough to digest sugars. They take a suck, and the sugars shut down their digestion, so they pull out and starve. It's impossible to gauge brix by looking at a plant. Remember heathy mj has a brix of 7. The first test I did on this crop, which is by far the healthiest I've grown, was exactly 7. So I started playing around. I would change one thing at a time, feed strength, frequency, additives, ect... After each change I would let the plants adjust, and take a brix reading. If the number went up, it was a good change. When the brix went down, that change was dropped. What I've seen amazes me how much even the smallest simplest change effects brix. The key to doing this is take the reading at the same time everyday, and from the same general area on the plant. From what I've researched the best times to take a brix reading is 2 to 5 hours after morning feed. This is when the number will at its highest. I've done tests throughout the day and found this to be true. It's super simple to do a brix test, not so easy changing the brix though. In just a week I've raised my brix from 7 on the first test, to 10 on my last test. The difference in the overall plant look, growth, everything is very noticeable. I thought the were stunning when the brix was 7, but now that they are at a 10 the whole structure, feel, color of the plant has changed! Between testing brix, and doing weekly 1:1.5 soil analysis it feels like I've taken control of my grow. No more guessing. Two of the easiest tests to give you all the info you need to grow great plants, and both are the least talked about on forums. Knowing the ph and ec of your root zone is crucial to diagnosing sick plants. Soil growers can just check their runoff to get these numbers, but us who grow in coco don't have that luxury. Coco runoff is never the same as the root zone, so we have to do a 1:1.5 soil analysis. These two test are so simple to do, and provide so much information, and yet are never on any of the sick plant diagnoses sheets that I can find. I would recommend that any serious grow research these, and implement them into your grow.