| This is one of the most commonly used systems. A constant flow of nutrient solution pumped from a tank flows over the roots of the plants in a tube or tray and then returns to the tank. |
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There is no growing medium other than that which was used to propagate the plant from a seed or cutting - usually a small block of rockwool or a small pot of perlite. The roots rapidly grow out from this. |
The lack of a growing medium saves on cost of replacement but means that the roots of the plants are prone to drying out if the pump stops working or the inlet blocks. The tank must be checked regularly to adjust nutrient strength and pH. |
This system can be used for a wide range of crops, commonly tomatoes and herbs. |