Calcium and magnesium deficiencies show up as rust spots, interveinal yellowing, and curling leaf tips, often triggered by soft water, high light, or aggressive base nutrients. Left unaddressed, they cap growth and invite secondary problems.

A dedicated cal-mag supplement corrects most cases quickly, but the durable fix is balancing your base feed and water profile. Diagnose by leaf position and pattern before dosing, since over-correction creates its own lockouts.