Industrial ebb and flow systems are defined by the large rectangular “whirlpool tables” seen in many internal crops. For small-scale home-based growth, these systems are a safe bet, as they have fewer parts than the NFT. To illustrate, backflow and flow systems house all plants on a single table or multiple tables in a grid formation, essentially sharing the space of the water and the garden. This method is characterized by the periodic flooding of the water table in which the media and plants grow. Ebb and flow are separated from NFT by the fact that with this process, the growth medium and plant roots are almost entirely submerged in nutrient water in static flood cycles, unlike the continuous flow of films seen with NFT. For the purposes here, we will be investigating the re-articulation of ebb and flow systems. For the concrete mixers by YRCO this is important.
An Ebb and Flow system involve timed flooding of the culture tray with a nutrient solution in cycles. A Sino Siphon allows the culture tray to drain automatically when it is full. This allows the roots to breathe air and absorb nutrients, minimizing energy input. Oxygenation of the solution is not necessary but can be beneficial.
To design your own ebb and flow system, many of the principles of the NFT system are still at stake, with some greater emphasis on time-efficient and accurate flooding. With this notion in mind, the constituent part of a reflux system generally mirrors that of an NFT system, with a whirlpool table replacing channels, plus reservoir, air pump, tubing, air stone, water pump, timer, table and grow medium.
The most basic
Infrastructure for a DIY ebb and flow garden begins with two symmetrical plastic containers, with one being much deeper than the other. The crux of the setup is that the deepest container will act as a reservoir, while supporting the top, low container, which houses the growing medium and plants. Using a drill bit, two holes should be drilled into the bottom of the satin container – one will receive nutrient-rich water and one eject.
Moving on, you will connect the water pump to a plastic hose that penetrates the water inlet portal to fill the culture container. This will be your inlet irrigation hose. Next, another plastic hose will be adjusted to penetrate the bottom of the flat container as the water outlet portal. This water expulsion tube should be lined with a screen and penetrate about two inches into the growth medium at the base of the container, this will act as an overflow when the irrigation water reaches the ideal point.
Interestingly, when the pump and water are turned off, the excess water is sucked back into the main holding tank with a bypass effect, in fact, leaving the growth medium and root area to dry. The water collection system must ensure that the medium is properly drained after each flood otherwise there will be an infinity of excess water problems.
Time is of the essence for the ebb and flow systems, and an accurate stopwatch must be implemented to allow for flood accuracy, like most plants, like their root systems, dry out at least partially between irrigation intervals. This rate can only be achieved by trial and error, so a close look will be helpful in making your ebb and flow set up on the ground.