High EC, low runoff – Ca/Mg lockout with AN pH Perfect in flower

Tap water 363µS, base EC 0.49. Using AN pH Perfect G/M/B. Water test shows no Ca/Mg → suspect imbalance. Deficiencies ~1yr, now yellowing. Last feed 1ml/L BioBizz CalMag + 3ml/L G/M/B, EC 2.8 (before ~2–2.2). Runoff 0.5–0.6. Mostly fertigated. Feeding started wk5. Its photoperidc