# Sterile reservoir

> A sterile reservoir keeps hydroponic solution as free of microbes as possible with oxidising sanitisers or UV, a valid strategy that only works if applied consistently.

- Canonical: https://genetixbay.com/knowledge/glossary/sterile-reservoir.html
- Also written: sterile hydro, sterilised reservoir, sterilized reservoir, clean reservoir, sanitised reservoir, oxidiser-treated reservoir
- Glossary category: Systems and media · Evidence: Supported
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

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](https://genetixbay.com/knowledge/glossary/free-chlorine.md) or low-dose chlorine, chlorine dioxide, [hydrogen peroxide](https://genetixbay.com/knowledge/glossary/hydrogen-peroxide.md)), 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](https://genetixbay.com/knowledge/glossary/biological-control.md) 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](https://genetixbay.com/knowledge/glossary/beneficial-microbe-reservoir.md) 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](https://genetixbay.com/knowledge/diseases/root-rot-pythium.md).

## Don't confuse with

- **Beneficial-microbe reservoir**: the opposite strategy.
- **Clean reservoir (hygiene)**: lightproof, covered, changed on time; required in either strategy.

## Related terms

[Beneficial-microbe reservoir](https://genetixbay.com/knowledge/glossary/beneficial-microbe-reservoir.md), [Hydrogen peroxide](https://genetixbay.com/knowledge/glossary/hydrogen-peroxide.md), [Reservoir](https://genetixbay.com/knowledge/glossary/reservoir.md), [Root rot](https://genetixbay.com/knowledge/glossary/root-rot.md), [Chiller](https://genetixbay.com/knowledge/glossary/chiller.md)

## Read more

- [Root rot and Pythium in cannabis](https://genetixbay.com/knowledge/diseases/root-rot-pythium.md)
- [Sanitation and disease prevention for cannabis grows](https://genetixbay.com/knowledge/diseases/sanitation-and-prevention.md)

## Sources

1. Colorado State University Extension PlantTalk 2043. Root disease problems and management in hydroponic systems. https://planttalk.colostate.edu/topics/miscellaneous/2043-root-disease-problems-management-hydroponic-systems/