Feeding cannabis: what the numbers on a bottle mean, how much of it the plant can take up at a given pH, and how to tell a real deficiency from a root-zone problem wearing its costume. Product lines and general nutrition both live here.
The board is split two ways. Brand sub-boards carry questions tied to a specific line, where the feed chart and the ratios are fixed by the manufacturer: CANNA, Grotek, House & Garden, BioBizz, Guanokalong GK-Organics, FloraFlex and Advanced Nutrients. General Nutrients Q&A takes everything that is not brand-specific, including biostimulants, microbial inoculants and mixing questions.
Two things save a lot of argument here. Almost every feeding thread turns on pH and electrical conductivity, because a nutrient that is present but locked out looks exactly like a nutrient that is missing, so post the numbers with the question. And the substrate decides the strategy: the same bottle behaves differently in peat, in coco coir and in a recirculating system, so say which one you are on.
Where to start