Biofilter

A biofilter is a home base for the beneficial bacterial in an aquaponic system. It is a container where the primary purpose is to increase the available surface area for the bacteria in your system to replicate. From here they’ll travel off to work throughout your system, but this is the area of highest concentration. A biofilter should be filled with media that is fairly porous, and offers a high surface area to volume ratio.

Here is a good example of an appropriate biofilter media:

Catch Basin

A catch basin is a water reservoir. It’s primary purpose is to increase the volume of your system, which provides increased stability as well as a reserve of water that meets the condition requirements of your system.

Grow Beds
Deep Water

These grow beds are composed of a container (usually about a foot in depth) with polystyrene (styrofoam) rafts that float on water. That’s it. Rafts will have holes cut in them where you nest your seedlings. From there, the water passing by underneath the rafts will supply your roots with the needed nutrients for growth.

Generally, deep water beds are used for leafy greens and produce which does not require support from root structures.

Media

These grow beds consist of a container filled with a rock medium or appropriate alternative (clay pebbles, etc.). Water filters in the space between the medium. These grow beds rely on flood-and-drain techniques to provide your plant roots with both nutrients and oxygen.

Generally, media beds are used for plants which will use their roots for anchoring (tomatoes, cucumbers, etc.).

Wicking

These grow beds consist of a container filled with traditional soil, with piping running through soil. But wait, doesn’t aquaponics eliminate the need for soil? It does. But some people choose to use wicking beds to grow root vegetables (carrots, potatoes, etc.). Since it’s in a container, you still don’t end up with the water loss that is associated with traditional gardening and farming.

Fish Tank

The fish tank serves as a tank for your fish. I know, this just blew your mind. Wow. But you’d be surprised how many people overlook this in the rush to consider everything else they need for their system.

Lighting

Lighting is an essential part of aquaponic systems. Because most systems are indoors with limited access to sunlight, supplemental lighting needs to be added to help the plants grow. Generally LED lights are the best alternative for growing plants away from the sun.

Miscellaneous

Some important miscellaneous components include:

  • Fish food
  • pH meter (or test strips)
  • EC meter
  • DO (Dissolved Oxygen) meter

Oxygen Bubblers

Oxygen bubblers, or air stones, serve to help pump oxygen into the water. This is essential because everything in your system (fish, plants, and bacteria) requires oxygen for life. Do not underestimate the importance of oxygen.

When I was first discovering aquaponics, a wise teacher gave me this advice: “How do you know when your system has too much oxygen? When your fish are getting blown out of the water!”

Plumbing

Most PVC or flexible tubing will work for plumbing. An important guideline to remember, however, is that you will have some undissolved solids floating in your system, and sludge will inevitably build up over time. For this reason, the larger (diameter) pipe you use, the fewer problems you’ll run into along the way.

Pump

A pump serves to cycle the water, and nutrients, throughout your system. If you’re going to spend money on any part of your system, spend it here. A good pump will pay dividends in the long run, requiring less maintenance and fewer replacements.

Two important elements to consider when purchasing your pump are the size of your system and the vertical height of your system. Your pump should be able to circulate all the water in your system in approximately two hours, meaning you’ll want a pump with a flow rate of half your system’s volume. Note though, that your flow rate decreases as the difference in height between the lowest and highest points of your system increases. Pump flow rates are generally displayed at their maximum capability, meaning that the flow rate you see is only achievable along a horizontal plane. You’ll need to find a pump that can meet both the flow rate and height requirements of your system.