Flood and Drain Aquaponics System

Flood and Drain Aquaponics System

A flood and drain aquaponics system, also called media-based system, is the easiest to build and maintain aquaponics system. This system is most suited for aquaponics beginners. It is also the most common type of aquaponics system used by many do-it-yourself aquaponics gardeners. Read this article to learn more about the flood and drain system of aquaponics if you’re a beginner in aquaponics and planning to set up your aquaponics system.

What is a Flood and Drain System

A flood and drain system is one type of aquaponics system. The most basic flood and drain system comprise a single grow bed, fish tank, water pump, and a bell siphon. In this system, the plants are planted in the grow bed filled with grow media that support plant roots and provide additional surface area for the beneficial bacteria to grow. These bacteria convert fish wastes into plant food. The fish, plants, and beneficial bacteria have to work together in the system for you to have a fully functional and productive aquaponics system.

Key points of a flood and drain aquaponics system:

  • The grow bed filled with grow media (expanded clay, gravel or lava rocks) is placed above the fish tank.
  • The water is pumped from the fish tank into the grow bed, where the plants feed on the nutrient-rich water produced by the fish.
  • The water then returns to the fish tank clean for the fish to live. 
  • Transferring the water between the grow bed and the fish tank is accomplished through the use of a pump, timer, and a bell siphon. 
Flood and Drain Aquaponics System
Flood And Drain Aquaponics System

How Do A Flood And Drain Aquaponics system Work

In flood and drain aquaponics systems, the water is moved back and forth between the grow bed and the fish tank. These are done through the use of a pump and a bell siphon. The water pump, pumps the water from the fish tank to the grow bed, while the bell siphons automatically control the flood and drain cycle of the water in the grow bed. The water continues to cycle to the system, regularly keeping the plants and fish happy and healthy. 

The Importance Of Bell Siphon In A Flood And Drain Aquaponics System

The bell siphon is a device that regulates the water flow in flood and drain aquaponics systems without the need for human intervention. As water is pumped into the grow bed, the water will rise until it reaches a certain point and begins to overflow. At that point, the change in air pressure and the water movement will create a vacuum that starts the draining cycle. The water is then sucked out of the grow bed until they are almost drained, at which point the bell siphon sucks the air, which stops the process and allows the grow bed to flood again.

The bell siphon allows the water to move efficiently through the whole system, which is suitable for the fish and the plants. In addition, the automatic water regulation of the water saves time and effort on the part of an aquaponics gardener. 

Here are some benefits of a bell siphon in flood and drain aquaponics systems.

  1. It provides aeration for the plants’ roots and promotes oxygen intake that aids in plant growth and the overall health of the plants.
  2. Bell siphons allow for the regular movement of the water in and out and into the grow bed. The regular in-and-out flow of the water helps improve the oxygen level of the water and prevent water stagnation.
  3. The bell siphon works automatically, which helps save time and effort on the part of the aquaponics gardener.
  4. Bell siphons are easy to maintain and require little maintenance and troubleshooting.

Advantage of A Flood And Drain Aquaponics System:

  • Easy to build and maintain
  • Inexpensive to build and requires minimal cleaning to maintain.
  • It does not require a sump tank.
  • Suitable for all kinds of plants, from leafy greens to larger fruiting plants.
  • The grow media performs the filtering action, preventing solids from entering the fish tank.
  • Suitable for backyard or indoor aquaponics gardening.
  • Great for do-it-yourself people, as recycled materials can be used as grow beds or fish tanks.

Disadvantages Of A Flood And Drain Aquaponics System:

  • A good quality media can be expensive.
  • It can require cleaning of the grow bed.
  • The media beds are heavy and require a strong and rigid structure.

Most Common Sample of a Flood and Drain Aquaponics System

  • IBC Tote Aquaponics

The IBC Tote system is one of the most popular aquaponics systems today because of their low price and customizable features. In this system, an Intermediate Bulk Container, also known as IBC tote, IBC tank or IBC pallets (an industrial-grade reusable container that is used for handling and storing bulk amounts of liquids and powders) are used as fish tanks and grow beds. IBC’s size ranges from 500 liters to 1200 liters, but the most common size that is available and often used in aquaponics systems is the 1000 liters IBC totes.

  • Barrelponics

A barrelponics system is based on a barrel or a 55-gallon drum. The barrel is cut in half and used as a fish tank and a grow bed. This system is great for beginners in aquaponics who want to start small. Because of the compact size of the barrelponics system, it can be placed in a small balcony, garage or indoors.


The reasons why the flood and drain aquaponics system are popular with aquaponics gardeners is because of its low cost and low maintenance features. This system is great for home use, so if you are planning on building your own aquaponics system, the flood and drain is definitely one to start with. Once you’ve learned the basics and want to increase your food production, then you will need a more sophisticated system, but one advantage of aquaponics is you can combine two or more different aquaponics systems to suit your needs. So start small and enjoy learning and experimenting with your own system, and expand later. Thank you for reading this article, feel free to leave your comment below.