A beneficial-microbe reservoir is a hydroponic strategy in which the solution is regularly dosed with live, beneficial organisms, typically Bacillus species, sometimes Trichoderma or mixed consortia, and is kept free of sanitisers that would kill them. The beneficials colonise roots and surfaces, compete with pathogens such as Pythium for space and nutrients, and can form a protective biofilm on healthy white roots.
In practice
Dose according to the product, usually weekly or with every reservoir change, and avoid chlorine, peroxide and other oxidisers that wipe them out. Keep the solution cool (about 18-21 °C, 64-70 °F) and well aerated; beneficials do not replace good temperature and oxygen management. Roots in a healthy bio reservoir are often tan-tinged or slightly fuzzy-white; slime and a sour smell indicate trouble.
Myth check
House position: a beneficial-microbe reservoir is preferred. Bacteria will show up in any reservoir regardless, so you may as well have the good ones. A sterile reservoir is valid too, but you must commit to it fully; it's a personal choice. Evidence: Supported for biological control of root pathogens in hydroponics; product results vary. See root rot and Pythium.
Don't confuse with
- Sterile reservoir: the opposite strategy.
- Compost tea: a brewed soil drench, not a hydro inoculant.
