IMO (any please correct me if I am wrong but...) Hydro nutes are tailored for Hydroponic systems and can either be chemical or organic. Organic nutes can be for either soil or hydro and only recieve the title organic by the process used to collect and process the fertilizer. Organic being of no outside chemicals not found in nature. Chemical fertilizer such as mircle grow is highly processed and chemical altered. Hydro organic is just one form or combination of fertilizer. Hydro fertilizer my be used for dirt but remember that is not the intented use so there will be backlash from using it. Try your best to match your nutes with your medium. Good luck.... :watchplant: