Our proprietary mix contains all essential nutrients and trace elements to grow incredibly dense cultures of spirulina. No measuring is required! Each kit makes 25 gallons of perfectly balanced growth media. The live culture is laboratory-grown and guaranteed pure and highly active. This formulation of nutrients took over a year to perfect and has proven to grow the most dense and stable cultures of spirulina. Also included is a bottle of metals and nutrients used to replenish those depleted after harvesting. This allows your culture to thrive indefinitely by dosing after each harvest. Please contact me with any questions. I’ll be happy to help in any way!