On the first chart, you want to be in that middle band for plants (14-30 ppm). The white area (where you are) is low for plants, the darker area is dangerous for fish. Ideally you'd want enough to get to the upper teens or into the 20 ppms. From what I've read, DIY will get you maybe as high as 20 (can add 10-15 ppm), pressurized is needed to maintain higher concentrations.