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All problems
Moderate
pH / EC

pH constantly drifting up or down

pH meter reads outside 5.5–6.0 within a day or two of mixing fresh nutrients.

Commonly affects: All hydroponic crops

What you'll see

  • pH climbs above 6.5 within 24–48 hours of mixing
  • OR pH drops below 5.3 within 24–48 hours
  • Multiple deficiency symptoms appearing at once (lockout)

Likely causes

  • Tap water alkalinity is high (common in many SA areas)
  • Reservoir running low — concentration drift
  • Roots actively taking up specific nutrients shifts the pH
  • Algae or biofilm in the reservoir
  • Cheap or uncalibrated pH meter giving wrong readings

How to fix it (step by step)

  1. 1Calibrate your pH meter with pH 4.0 and pH 7.0 buffer solution — do this monthly
  2. 2Assess source-water alkalinity; standing water does not reliably remove bicarbonate or solve persistent pH drift
  3. 3Adjust pH daily until you understand your system's drift pattern
  4. 4Determine replacement needs from water quality, hygiene, crop and system conditions reduces drift

Stop it happening again

  • Test pH every day at the same time
  • Keep a pH meter calibration log
  • Use a high-quality pH down (food-grade phosphoric acid)

Need a second opinion?

Share dated photos, root observations, water readings and your mixing record so our team can assess the problem. Visual symptoms alone do not confirm a diagnosis.

Confirm the cause before treating the crop

Collect observations that distinguish possible causes

Record the first appearance of symptoms, the affected plants and whether old or new tissue is involved. Inspect roots, delivery and visible pests. Compare a healthy plant nearby. Record pH, EC, temperature and recent changes. Several causes may act together; the symptom title is a starting point, not a confirmed diagnosis.

Verify calibration and the complete mixing record. Product links explain nutrient roles; they are not instructions to use one bottle alone. Record your correction and assess subsequent growth because damaged leaves and fruit may not recover.

Escalate safely

Rapid wilting, collapse or spreading root symptoms need prompt checks of flow, oxygen and hygiene. Protect unaffected plants where practical and seek qualified diagnosis. Treatments must be registered for their intended crop and use and applied according to label, including harvest intervals.

When asking for help, provide dated root and leaf photos, water readings and mixing records. Do not combine nutrient changes with disinfectants or pesticides without compatibility advice. An online guide cannot confirm a pathogen or prescribe a universal chemical treatment.

Further reading

These sources support general cultivation guidance, not verified Nana Organics product performance. Current NaO instructions take precedence over another brand’s feeding schedule.