Design and Build Your Own Aquaponics System

Aquaponics is a revolutionary system for growing plants by fertilizing them with the waste water from fish in a sustainable closed system. A combination of aquaculture and hydroponics, aquaponic gardening is an amazingly productive way to grow organic vegetables, greens, herbs, and fruits, while providing the added benefits of fresh fish as a safe, healthy source of protein. On a larger scale, it is a key solution to mitigating food insecurity, climate change, groundwater pollution, and the impacts of overfishing on our oceans.


Aquaponic systems vary in size from small indoor or outdoor units to large commercial units, using the same technology. The systems usually contain fresh water, but salt water systems are plausible depending on the type of aquatic animal and which plants.

Function

Aquaponics consists of two main parts, with the aquaculture part for raising aquatic animals and the hydroponics part for growing plants. Aquatic effluents resulting from uneaten feed or raising animals like fish, accumulates in water due to the closed system recirculation of most aquaculture systems. The effluent-rich water becomes toxic to the aquatic animal in high concentrations but these effluents are nutrients essential for plant growth. Although consisting primarily of these two parts, aquaponics system are usually grouped into several components or subsystems responsible for the effective removal of solid wastes, for adding bases to neutralize acids, or for maintaining water oxygenation. Typical components include:

• Rearing tank: the tanks for raising and feeding the fish;
• Solids removal: a unit for catching uneaten food and detached biofilms, and for settling out fine particulates;
• Biofilter: a place where the nitrification bacteria can grow and convert ammonia into nitrates, which are usable by the plants;
• Hydroponics subsystem: the portion of the system where plants are grown by absorbing excess nutrients from the water;
• Sump: the lowest point in the system where the water flows to and from which it is pumped back to the rearing tanks.

 

Depending on the sophistication and cost of the aquaponics system, the units for solids removal, biofiltration, and/or the hydroponics subsystem may be combined into one unit or subsystem, which prevents the water from flowing directly from the aquaculture part of the system to the hydroponics part.

Design your own Aquaponics System

Have you got a great idea for an aquaponic system? Want to design your own system or see how one of systems will look in your area?

Google Sketchup is a fantastic tool to use for simple 3D design, and almost anyone can use it without after just a few minutes experimenting.

Make your own in seven step

First step: dig a hole for the fish tub to go into , ensure that your fish tub has some shade to avoid evaporation and is also below ground level to maintain a good steady water temperature.

The second step: run a 10 metre long outdoor/waterproof extension cable from my shed to the fish area and connect the pump and the air pump to the power outlet. I then places all leads and sensitive electrical parts in a waterproofed box and buried it in a small hole that was easily accessible to me.

The third step is to drill or make some holes in the bottom of your growtub so that that the water can drain out back into the fish tub next thing is to setup a place for the grow tub to sit preferably close as possible to the fish tub as this way the pump wont have to work as hard to get the water into the grow tub from the fish tub.
For my example setup I simply placed the the grow tub at a higher level than the fish tub and let gravity control the water flow back down into the fish tub with the help of a basic roof tile.

The fourth step was to connect a hose from the 1000L pond pump to the grow tub and set it up with the digital power timer to control when i wanted the pond pump to turn on and off.

The fifth step was to then fill the fish tub with dechlorinated water and fish and run a few trial runs to see if the water flowed from the fish tub to the grow tub and back out correctly. At this point its a good idea to monitor how fast the water is escaping as this will slow down a lot after you add your grow medium

The seventh step was to wash the gravel and then add the gravel into the growtub (make sure your happy with the location as it gets extremely heavy and impossible to move) . From here you can simply drop some seeds into the grow tub and cover lightly with gravel and wait for germination to occur. When you first put the seeds in you will have doubts that the plants will even come up but be patient and you will see plenty of little seedlings otherwise you can always add plants transplanted from a dirt garden. Germination is always faster in hotter weather.

Here are just a few of the fish species for your Auquaponic systems

• Talapia
• Rainbow Trout
• Brown Trout
• Silver Perch
• Jade Perch
• Sleepy Cod
• Murray cod
• Barramundi
• Yabby
• Crayfish
• Redclaw