From testing & studying various brands we believe it is Dyna-gro. The linked article below labeled “What Are The Best Nutrients For Hydroponics?” goes over complete plant nutrition and should give you plenty of information on why we feel this way about Dyna-gro. They have a trade-secret process and is the only nutrient that has figured out how to add all 6 essential macro-nutrients into 1 formula. Macro-Nutrients are required by plants in large amounts. This is why Dyna-gro advertises that they are the only complete formula in 1 bottle because no other nutrient company has been able to figure it out. Dyna-Gro Foliage Pro is complete, simple, and well balanced which is everything we were looking for when recommending to our backyard and commercial growers.