I just use the EC/CF scale on my truncheon - saves a similar confusion I had with the 5x/7x ppm
Bluefunk Reviewed by Bluefunk on . I'm Lost - New Bluelab Truncheon. Nute questions My first grow was NL x Shiva and WW. Both went well IMO, and the WW went especially good. Though I've nothing to compare to. Used a 400 hps, and no ph or ppm meter. I did occasional drop/paper ph tests. I winged the nutes using various people's formulas posted here. I bought a ph meter and today got a Bluelab Truncheon so I can grow better. I'm now growing new plants which are about 5-6 weeks old still under MH light. I tested the water with the truncheon. CF 12, EC 1.2, ppm @ 700 Rating: 5