So you’ve grown in soil for a while now and you keep hearing about how hydroponics can provide massive yields without using soil at all. Yet, there are different ways that hydroponics can be organized and set up so it might be a little intimidating to know where to begin if you’re interested in trying a different growing technique. For us, there are two dominant types of hydroponics systems that really have had a positive, measurable impact on our growth and yields. They are Deep Water Culture Hydroponics and Ebb and Flow Hydroponics. We’re going to break down the differences and benefits and drawbacks of each. Be prepared, though, there are a lot of things that we won’t cover in this article because there is just too much to say about hydroponics for us to put into one place—so if you’re looking for a comparative chart between hydro and soil, please stay on the lookout for our other articles covering that topic. We’re going to focus on describing these two systems, what makes them different, and what you should pay attention to when making these systems at home.
What is “Hydroponics?”
Hydroponics is when you use nutrient-rich water to feed and water your plants’ roots instead of growing them in soil. It requires a way to produce a constant flow of water to ensure oxygen circulates throughout the system and it necessitates that you continuously measure nutrient levels in your system so that your plants do not get burned nor do they run out of nutrients.
What Is a Deep Water Culture System?
A Deep Water Culture (DWC) system is made up of a few components:
- A reservoir (usually 8-10 inches deep) filled with a nutrient solution
- A platform from which the plants are suspended over the water in the reservoir (usually plastic or Styrofoam)
- Containers to hold the plants, usually filled with clay pellets or Rockwool
- An air pump to circulate oxygen into the water
- An air stone that helps create bubbles in the water
- Tubing that connects the air stone and the pump
A DWC system is relatively simple system. The air pump pushes oxygen through the air stone into the nutrient solution, causing nutrients and oxygen to percolate around your plants’ roots, which dangle from their baskets into the solution. The plants themselves are suspended over the reservoir by the Styrofoam platform and usually sit inside a basket that is filled with Rockwool, coco coir, or clay pellets, which provide a stable base that will not rot or collect bacteria. Your plants are always submerged in water, their roots always exposed to nutrients (unlike Ebb and Flow systems). This system can be set up with a single reservoir to hold multiple plants or each plant can have its own container (this is usually preferable so your plants can grow larger).
Like all reservoirs in hydro systems, you’ll need to make sure that the nutrient solution is completely sealed from light (as best you can) to help keep bacteria from growing and feeding on the nutrients. You will periodically need to replace the water and nutrients as your plants will consume nutrients and your solution just may not have good proportions. Be sure to keep careful watch on TDS and pH levels.
What is an Ebb and Flow System?
An Ebb and Flow system is similar to DWC, except that instead of having your plant roots exposed to the reservoir directly, your plants sit atop a tray or tube through which nutrient water passes by the effort of a water pump. Additionally, you need a drainage system that allows the nutrient solution to return to the reservoir. Here are the components required:
- A reservoir to hold your nutrient solution
- A water pump that moves the nutrient solution
- A tube and a filter-nozzle that expels the nutrient solution
- A grow tray where your plants will sit and where their roots will dangle into
- Baskets to hold your plants
- An overflow drain that allows the nutrient solution to return to the reservoir
- A timer to control the On/Off schedule (if your pump doesn’t include one)
- Some kind of media like coco coir or clay pellets
The reservoir below holds your nutrient solution and the water pump pulls that solution up into the grow tray. The grow tray fills with the solution (and oxygen through a bubbling action) and exposes the roots to the nutrients. Your plant roots should be dangling down into the grow tray cavity and should be exposed to the nutrient solution. When the nutrient solution reaches the top of the tray you should have an overflow regulator ensuring that the solution doesn’t spill out. The water will drain back into the reservoir, eventually allowing the roots to dry out before the solution is fed again. Drying out is a positive because it reduces risk of pathogens.
Pros and cons of each system
|Deep Water Culture||Ebb and Flow|
|Pros||· Quick growth
· Perfect for small spaces
· Flexible for different plant sizes
· Uses less water
· Beginner friendly
· Can build at home (don’t need to buy special containers)
|· Timer does most of the work
· Can be used with different grow media
· Nutrient solution can be reused continuously
· Great for plants with low water tolerance
· Helps reduce risk of pathogens
· Great for larger yields
|Cons||· Can expose roots to too much water and cause rot
· Produces smaller plants
· Difficult to feed/replace water
· Hard to expand to more plants
|· A little difficult to set up
· Wastes more water
· Takes up a little more space
· Can be costly
We hope this helps introduce you to the two main systems in hydroponics. We tend to lean towards DWC because of our own experience but there are so many growers out there that love Ebb and Flow and for good reason! Be sure to engage with communities who will teach you all about growing and hydroponics if you’re new to it—it’s your best resource!