Hydroponic Growing Techniques
Aeroponics systems have the plants roots dangle in a chamber and a pump sprays the them with nutrient solution. There is high pressure and low pressure systems.
High pressure systems anatomize the nutrient solution delivering a fog to the roots. It is very easy for the plant to uptake the nutrient solution. The equipment is more expensive and requires more attention to maintain healthy plants.
Low pressure systems require a basic water pump and spray heads. The nutrient solution is also sprayed directly to the plants roots. If there is a blockage in either high or low pressure system the plants can die.Drip irrigation is the most used hydroponic systems used by commercial growers. There is two kinds run to waste and recirculating where the nutrient solution is reused. Run to waste requires regulation so there is little waste of the nutrient solution. In a drip system you need a water pump and timer to control when the system comes on and how long it stays on.
Drip irrigation is a type of micro-irrigation system that has the potential to save water and nutrients by allowing water to drip slowly to the roots of plants, either from above the soil surface or buried below the surface.
The goal is to place water directly into the root zone and minimize evaporation. Drip irrigation systems distribute water through a network of valves, pipes, tubing, and emitters. A drip irrigation system can be more efficient than other types of irrigation systems, such as surface irrigation or sprinkler irrigation.
Ebb and flow or flood and drain is sub-irrigation that drains back into the reservoir where it is recirculated. The picture below shows a 2x4 tray with a inlet tube and a overflow tube
Look closely at the picture above and notice 2 tubes with screens on top. The tube on the right side is hooked to a water pump and is the inlet tube. As the water rises in the tray it empties from the overflow tubes back into the reservoir container below the tray. The overflow tube controls the level that the water reaches.
The inlet tube is 1/2 in and the overflow tube is 3/4 in, that keeps the nutrient solution from overflowing the tray. The tray holds many individual grow containers that are filled with hydroponic medium. The system requires a water pump to fill up the tray from the reservoir below. A timer is required to control how many ebb and flow cycles there are a day.
When the timer comes on the water pump comes on and starts filling the tray from the inlet tube. The grow containers in the tray start filling up from the bottom and stale air is pushed out of the growing containers When the timer shuts off the pump stops and the level of the water drains out pulling fresh air in from the top delivering it to the roots. Then the cycle repeats depending on the timer settings.
Nutrient film technique (NFT) is a hydroponic technique where in a very shallow stream of water containing all the dissolved nutrients required for plant growth is re-circulated past the bare roots of plants in a watertight gully, also known as channels.
The flow and length of channel is critical to growing healthy plants. Flow rate, channel slope, and channel length are all important to growing plants. Flow rate should be 2 leter per minute maximum if the flow rate is to fast there could be nutrition problems. Slope of channels should be 1:30 to 1:40.
The length for the channels should be no longer than 10 to 15 meters. To much length has shown to deplete the nitrogen along the gully. Plants placed into nutrient-rich water channels in an NFT system.
Look at the picture above It looks like roof gutter with holes for the net pots You can use 4 inch drain pipe with holes for the net pots which works the same way.
Deep water culture is a hydroponic method of plant production by means of suspending the plant roots in a solution of nutrient-rich, oxygenated water.