Hi Claudia, I would like some clarification on this as well. It’s my understanding that EC is also a factor that might give more clues to what is happening. Low brix, low EC, high or low pH = ions missing. Low brix, high EC, high or low pH = ions not being complexed. I’m assuming this could be either cations or anions but may be wrong. Looking at my chart it seems that you could have either a lack of N (ions missing) or nitrate excess (ions not being complexed) at either a high or low pH depending on what the EC level is. Appreciate any clarification or correction of this.