A sterile reservoir is a hydroponic strategy that aims to keep the solution nearly free of microorganisms, both good and bad, so pathogens have no foothold. Common tools are oxidising sanitisers (hypochlorous acid or low-dose chlorine, chlorine dioxide, hydrogen peroxide), UV-C sterilisers on the return line, and ozone in commercial systems, alongside clean equipment and fresh, low-organic water.
In practice
Commit fully. A half-sterile system, dosed occasionally, kills off beneficials and then lets pathogens recolonise an empty niche. Doses must be maintained to keep a residual through each change, and sanitisers break down faster in warm, organic-rich solution. Never combine a sterile programme with beneficial microbe products: they cancel each other out. Wear gloves and eye protection when handling concentrated oxidisers.
Myth check
House position: a beneficial-microbe reservoir is preferred, because bacteria will turn up regardless. A sterile reservoir is valid, but you have to commit to it fully; it's a personal choice. See root rot and Pythium.
Don't confuse with
- Beneficial-microbe reservoir: the opposite strategy.
- Clean reservoir (hygiene): lightproof, covered, changed on time; required in either strategy.
