The core parts
| Part | What it does | Beginner note |
|---|---|---|
| Reservoir | Holds the nutrient solution. | Use opaque containers to slow algae growth. |
| Nutrients | Provide minerals the plant would normally get from soil. | Follow the label before copying internet recipes. |
| Growing media | Supports the plant while roots grow into water. | Clay pebbles and starter plugs are common. |
| Light | Drives growth through photosynthesis. | Leafy greens need less intensity than fruiting crops. |
| Oxygen | Keeps roots from suffocating. | Kratky leaves an air gap; DWC uses an air pump. |
The numbers to track
pH tells you how acidic or alkaline the solution is. Many leafy greens and herbs are often grown around pH 5.8 to 6.5, but crop and nutrient guidance matters.
EC measures electrical conductivity, which gives a rough view of nutrient strength. PPM is a converted number, and different meters use different conversion scales.
Do not chase perfect numbers on day one. Learn how your meter works, calibrate if required, and write down readings at the same time each day.
Common home system types
- Kratky: passive container with no pump. Good first system for lettuce and herbs.
- DWC: deep water culture with an air pump. More oxygen, more parts.
- Ebb and flow: periodically floods roots. Flexible, but more hardware.
- NFT: thin nutrient film over roots. Common commercially, less forgiving for beginners.
Common beginner mistakes
- Using a clear container and growing algae in the water.
- Adding more nutrients every time the plant looks stressed.
- Ignoring light distance and burning or stretching seedlings.
- Growing fruiting crops before learning leafy greens.
- Not writing down pH, EC, and water-level changes.