What is Ebb and Flow Hydroponics?

Also known as flood and drain, ebb and flow hydroponics systems use a tray to hold plants above a reservoir of nutrient solution. The tray holds pots containing plants and a growth medium. The growth medium can be small pieces of clay, Rockwool, or something similar. The purpose of the growth medium is to hold the root system in place.

Using a timer system set at regular intervals, a pump fills the tray with the nutrient solution. Then, the nutrient solution drains back down into the reservoir so it is ready to pump again at the next pre-set interval. This system allows the plant roots to regularly be saturated with air and nutrients to help the plants grow and flourish.

Benefits of Ebb and Flow Hydroponics

These systems are simple, reliable, and do not cost much to set up initially. With a timed pump system, water floods the root systems, and then drains away from it. All you have to do is periodically check the pH of the nutrient water, and inspect root systems. Because the plants are being fed multiple times per day, you can use a lower parts per million (PPM) nutrient solution to feed the plants.

Disadvantages of Ebb and Flow Hydroponics

These systems are best used with plants that are smaller in nature, though larger plants can be grown in large buckets, using a high volume pump. Users must carefully inspect the plants, as roots are more likely to grow together under this configuration. If you have to remove a harvested or damaged plant from the system, it can be a problem if your plant has a well developed root system.

While the recycling reservoir system is beneficial in the sense that it automates much of the plant care, it also has a tendency to throw off the pH of the nutrient solution over time. If the pH fluctuates too much, it is not healthy for the plant. If you do not correct the pH problem, various issues may occur, including leaf cannibalization and poor nutrient absorption.

When plants flower, the pH rises considerably every day. Adjust the system’s pH first thing in the morning, and again at night right before bed. Because nutrient and water absorption also increase during this period, expect more root exudate to be carried back to the reservoir. You will need to periodically clean the reservoir and adjust the nutrient solution to ensure the plants remain as healthy as possible.

Is an Ebb and Flow Hydroponics System RIght for You?

This system is right for you if you do not have a lot of start up capital to work with, and you want the system to run automatically during the day while you’re at school or work. You will still need to invest time every day on pH adjustments, though. Because the system is far less complex than other options out there, it is a good choice for those who are just getting started with hydroponic gardening.