The malted barely is about the same as molasses, it feeds the microbes in the soil, and has enzymes that break down the complex carbohydrates into sugars that are more digestable to the microbes. It's really about a wash for effectiveness. Molasses is a lot cheaper. Mixing depends on how diluted the extract is, it is also available in powder form. The bottom line is either barley or molasses, the effects on the microbes only last a couple days, the microbe numbers will spike, until the sugars are used up, then the population crashes.