Hydroponics | How it works

There are a few different techniques of using hydroponic systems. Most manufacturers of grow box systems are fully aware of the different types and mix/match the different techniques with grow boxes they sell for maximum efficiency. This is one of the reasons it is important to buy a hydroponic system form a manufacturer, because you don't want to buy the wrong parts for your homemade hydroponic system.

The 2 types major types of hydroponics are the solution culture and the medium culture. The solution culture does not use a solid medium for plant growth, rather only the nutrients. The 3 types of solution culture techniques are:

1. Static Solution Culture
2. Continuous Flow Solution Culture
3. Aeroponics

The medium culture solution uses solid materials such as sand, gravel, or rockwool culture. The 2 main variations of this are subirrigation and top irrigation. It is now known that plastic is the best material for the hydroponic container when growing in a hydroponic system.

Static Solution Culture

In this form of hydroponic growing, plants are grown in containers of nutrient solution. Again, plastic is your best bet when setting up a container for hydroponic growth. The solution is usually gently aerated. The solution is also kept low enough that enough roots are above the solution so they get adequate oxygen. Holes are cut in the lid of the container to hold plants. There can be many plants, or just one, in each resorvoir. The nutrient solution in this system should be changed once a week. As the nutrient solution falls below the optimal level, water and/or nutrients should be added to keep it up.

Continuous Flow Solution Culture

In this form of growing, the nutrient solution is constantly passing through the roots. The nutrient solution is kept low enough so that the roots get oxygen as well as nutrients. This solution is one of the more productive techniques when dealing with thousands of plants. Flow rates through the roots should be at a rate of 1 liter per minute for optimum results.

Aeroponics

The aeroponic system is basically a system where the roots are continuously fed nutrients and solution through a mist, aerosol, or fogger. It is not a continuous mist that sprays on the roots, but a periodical mist. Excellent aeration is the main advantage of aeroponics. The aeroponic system is great when dealing with up to 100 plants, but more challenging when dealing in the thousands of plants.

Passive Subirrigation

This form of hydroponic growing is a method where plants are grown in an inert porous medium that transports water and fertilizer to the roots by capillary action from a separate reservoir as necessary, reducing labor and providing a constant supply of water to the roots. This method is considered the simplest method in the hydroponic growing industry, but not necessarly a highly desired form when compared to other growing systems like aeroponics.

Ebb and Flow - Flood and Drain Subirrigation

This method involves a tray above a reservoir of nutrient solution. The tray is filled with a growing medium and planted directly. Alternativly, the pots of the medium stand in the tray. A timer causes a pump to fill the upper tray with a nutrient solution at regular intervals, after which the solution drains back down into the reservoir. The medium is continuously flushed with nutrients and oxygen. The upper tray fills past the drain, and then recirculates the water until the pump is turned off, and then the water in the upper tray drains back into the resevoir.

Top Irrigation

The Top irrigation hydroponic method consists of nutrient solution periodically applied to the medium surface. This can be done manually once per day in large containers of some media, such as sand. Usually, it is automated with a pump, timer and drip irrigation tubing to deliver nutrient solution as frequently as 5 to 10 minutes every hour.

Deep Water Culture

In this method of growing, the plants are suspended with the roots dangeling in nutrient rich, oxygenated water. The 2 items of importance are a plastic bucket and a nets to hold the plants up. The net used should be a high quality net capable of holding up to 60 pounds of weight. Most manufacturers use a special type of netting when producing grow systems.