Raft systems are where plants are grown whilst being ‘floated’ on top of a nutrient tank. The roots dangle in the nutrient and take up the solution as and when required.
This type of system generally requires a lot of water and it is highly important that the nutrient/water solution is kept highly oxygenated. If the system was not oxygenated, the plants could ‘drown’. The raft system is considered to be a little outdated, but does have some merits in certain circumstances.
Often raft systems are cheap to build and can run without pumps as long as enough oxygen is added to the system.
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