Why Mycorrhiza Rarely Works in Typical Hydroponics
At phosphorus concentrations above 50–100 µM in solution, "mycorrhizal symbiosis either does not form or remains minimal."
Where it is justified:
- Substrate-based systems with low phosphorus concentration
- Seedlings before transition to a full nutrient recipe
Where Probiotic Bacteria Are Effective
- Bacillus — suppresses Pythium, Fusarium, and Botrytis
- Trichoderma — mycoparasites that directly parasitise pathogenic fungi
- Azospirillum — fixes nitrogen and stimulates root development
Conditions That Kill Probiotics
- H₂O₂ and PAA (Bacillus dies at H₂O₂ concentrations above 0.01%)
- UV-C treatment
- Low dissolved oxygen (<4 mg/L)
Three Mistakes That Cost the Most
- Applying mycorrhiza during active production on a full nutrient recipe
- Applying probiotics and chemical sanitisers at the same time
- Expecting a visible result from a single application
Signs of Effect
Indirect indicators: reduced frequency of root rot between cycles, consistently white roots, stable solution ORP.