Common Hydroponic Systems
Wick systems, the most basic, is simply a system that uses a cotton rope as a wick with one end submerged in a reservoir of nutrient solution, the roots are supplied nutrient and moisture at the other end.
Bubble systems are a popular, low cost system. These usually consist of a bucket as the main reservoir with a smaller container suspended above used as the plant site. A common aquarium air pump is used to air lift the nutrient solution to the top of the system where it is distributed evenly through a circular tubing with lots of tiny holes The nutrients then fall over the roots and back into the reservoir. This type of system is easy to build and operate. The constant aeration provided by the air pump and through the constant movement insures more than adequate oxygen is supplied to the roots. The drawback of this system is that there is often only room for one plant, although one air pump can run several systems. Another drawback is noise. These things are loud! Not good for a lot of reasons. Especially for those who enjoy privacy and need to avoid unwanted attention.
Ebb and Flo or Flood and Drain systems consist of a reservoir and another shallower type of reservoir called a growing bed. The nutrient solution is pumped into the growing bed until it fills to the desired level, then an overflow system keeps the bed from overflowing. Once the system timer shuts down the pump, the entire nutrient solution drains back into the reservoir. This system works so well because as the nutrient solution fills the bed, old air is forced out of the growing medium, and when the bed is drained this action draws fresh oxygen back into the medium. The major drawback of this type of system is the possibility of timer or pump failure. Since the plant's roots must receive constant moisture, if one or both were to fail, your garden would suffer within a few hours, and more than likely be completely destroyed within a day. If a small level of nutrient solution is allowed to remain in the bottom of the growing bed, say an inch or so at all times, this could easily prevent the problem. Another possible problem is overflow. This is a problem that can only be solved by always maintaining a clear overflow system. If the system were to become clogged with debris or roots this would, of course, result in overflowing of all the nutrient solution above what the bed can hold.
Bubble systems are a popular, low cost system. These usually consist of a bucket as the main reservoir with a smaller container suspended above used as the plant site. A common aquarium air pump is used to air lift the nutrient solution to the top of the system where it is distributed evenly through a circular tubing with lots of tiny holes The nutrients then fall over the roots and back into the reservoir. This type of system is easy to build and operate. The constant aeration provided by the air pump and through the constant movement insures more than adequate oxygen is supplied to the roots. The drawback of this system is that there is often only room for one plant, although one air pump can run several systems. Another drawback is noise. These things are loud! Not good for a lot of reasons. Especially for those who enjoy privacy and need to avoid unwanted attention.
Ebb and Flo or Flood and Drain systems consist of a reservoir and another shallower type of reservoir called a growing bed. The nutrient solution is pumped into the growing bed until it fills to the desired level, then an overflow system keeps the bed from overflowing. Once the system timer shuts down the pump, the entire nutrient solution drains back into the reservoir. This system works so well because as the nutrient solution fills the bed, old air is forced out of the growing medium, and when the bed is drained this action draws fresh oxygen back into the medium. The major drawback of this type of system is the possibility of timer or pump failure. Since the plant's roots must receive constant moisture, if one or both were to fail, your garden would suffer within a few hours, and more than likely be completely destroyed within a day. If a small level of nutrient solution is allowed to remain in the bottom of the growing bed, say an inch or so at all times, this could easily prevent the problem. Another possible problem is overflow. This is a problem that can only be solved by always maintaining a clear overflow system. If the system were to become clogged with debris or roots this would, of course, result in overflowing of all the nutrient solution above what the bed can hold.
Nutrient Film Technique(NFT) consists of a large enclosed channel, commonly a 4” or larger PVC pipe, where the plant sites are situated above the channel and the roots are suspended within, and receive nutrient from, a constant shallow flow along the bottom of the channel. The nutrient is pumped to the channel where gravity is used to send the solution through the channel, kind of like gutters on your house, where it is then drained back to the reservoir. The main problem with this system, as with many others, is that as the roots grow they can slow nutrient distribution.
The Raft System is, basically, a Styrofoam flat with several plant sites that floats on top of the nutrient solution. Roots receive oxygen that is pumped into the nutrient solution with an aquarium pump and aeration stone. This system is only suitable for short stature plants such as lettuce. It is really reliable and the only problem is that the aeration stone will usually clog quickly and reduce aeration. The only way to fix this problem is constant cleaning and changing of the stone. Some have suggested using a piece of air tubing with lots of small holes but I have found that no matter how small the holes and no matter the number of holes, you can never produce the air diffusion an air stone is capable of producing.
The Ein Gedi System is one of the most popular systems in use today by home gardeners. This systems is so popular that even the homemade type systems are being sold in shops and online. They look cool and are a little bit more difficult and expensive to build, but well worth the effort if you want a nice looking, high performance, easy to use system. The Ein Gedi consists of an enclosed chamber in which the plant basket sits in a shallow pool of nutrient solution. The baskets are heavily misted individually and the nutrient collects at the bottom until it reaches the overflow level and is drained back into the reservoir. This system always supplies a lot of oxygen and nutrient solution to the roots, and is pretty reliable, failing only if the pump or plumbing system fails.
Aeroponic systems are an excellent and affordable option, and are easy to build and operate. With Aeroponics the roots are suspended and are constantly sprayed with a fine mist of nutrient solution which then drains or drops back into the reservoir. This system offers the highest amount of oxygen to the root system. One problem with this system is that spray heads can become clogged by mineral buildup and cause pump failure.
The Dutch Bucket System is, basically, a pot or bucket fitted with a drain that allows a shallow pool of nutrient solution to stay in the bottom. The solution is fed through drip emitters from the top. This is a very, basic and fail safe irrigation type system which incorporates a recycling system for minimizing nutrient waste.
Fogger systems are pretty new and gaining a lot of popularity. In this type of system a fog of nutrient solution is created by a ultrasonic transducer. These are commonly found in use in newer humidifiers. The roots are suspended and fed nutrient and moisture through the fog. This type of system can produce incredibly healthy roots. Not only is it a cool new technique, this may very well be the best available system as far as root development goes.
