How to make your own Aquaponics System - Affordable and Easy Method
So you love keeping fish and you love growing delicious home grown vegetables why not go for the obvious choice start your own aquaponics system in your backyard and combine your two hobbies
So what is Aquaponics?
To put it simply aquaponics is the combination of Aquaculture and Hydroponics. The great thing about aquaponics is that it simulates a real life eco system where the bacteria process the fish waste from niitrites into nitrates which can then be absorbed by the plants and then returning clean water back to the fish.
My first system has been running for a little over a year now with no water changes apart from the rain that comes in and some water lost through evaporation and all the fish are still alive and well along with my plants.
Many aquaponics systems are used to grow fish such as tilapia , silver perch, jade perch , trout and other coldwater fish but in some cases people may use ornamental fish such as goldfish if they do not wish to eat fish or do not have the room for growing large edible fish.
Hydroponics is the method of growing plants without the use of soil, for example clay balls or fine gravel is a commonly used growing medium. Aquaponics is the same in this way as no soil whatsoever is being used.
The picture above demonstrates how aquaponics works , the fish produce the waste into the water the pump then circulates the water to reach the roots of the plants where the plants will absorb the nitrates and clean water will be returned to the fish tank.
How i got started
So the way you go about setting up your aquaponics setup can very straightforward or very complex depending on the approach you use. I will be discussing how to get a basic setup up and running on the smallish scale.
The system I will describe is currently running outside and consists of one small pond , small grow bed. It is a good example of how you can get a small system up and running cheaply and get the most out of it.
My system contains the following components
- 250L Pond Bin - 150L growtub
- 1000 L/ph pond pump (capable of pushing water to a height of 1 metre)
- double outlet air pump - 10 m extension cable
- large garden hose - bird wire (keep birds away from the fish)
- Tomato plants ( started from bought seed packets) - 50kg of fine gravel
- digital Timer/surge protector - used to run the pump to circulate the water to the plants at the moment running every 2 hours.
- 6 Comet goldfish - Bricks and roof tiles.
The above components excluding things that I already owned such as the growtub, extension cable ,garden hose,roof tiles and bricks. The cost of all other components was in total around 120 $US
Happy AP fish
Putting it all together
So once I had all my components needed to setup a simple small aquaponics setup the first step was to 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 was to 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 it's a good idea to monitor how fast the water is escaping as this will slow down a lot after you add your grow medium (in my case fine gravel).
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.
- Feeding the Fish
- Keeping an eye on the pump cycle , explained more in depth lower down
- Keeping an eye fish health and water level in fish tub.
Simple AP setup
The pump cycle is determined by how fast your grow tub fills up with water , ideally you want the water to fill up to about 3-5 cm before the top of the gravel and you can play around with the time setting until you find a nice spot.
Many people use the 15 minutes on 45 minutes off cycle but this is mainly with people with larger scale systems trying to provide the fish with more oxygenated water. Many of the modern digital power timers you can buy allow you to set up to 15 different on/off peroid in 24 hours and I have found this to be sufficient.
there are many other ways to control your pump cyle including toilet valves and autosiphons but that's a tale for another day.
Fish feed for an aquaponic system is always being discussed as some try to keep there systems totally organic by feeding there fish organic fish feed such as duckweed and worms. This method is perfectly fine its in fact truer to what aquaponics is about but sometimes its not realistic to be breeding worms and growing duckweed or buying expensive organic feed.
Many people just use cheap fish food from supermarkets and have found it to work just as good as organic feed. I currently use supermarket fish food for my goldfish and my system is running perfectly fine.
Most plants will work very well in an aquaponics type system especially things like tomatoes, spinach and most green vegetables. Your choice of plants to grow in your system will really depend on size and experimentation into which plants/vegetables grow well.
Like any plants even aquaponically grown plants can show deficiencies in some vitamins and minerals, So it is wise to add an organic fish friendly fertilizer like a seaweed fertilizer to your system every 2 weeks or so as you would a dirt garden to fix any signs of deficincies.
Increasing the scale
It is very easy to increase your aquaponics setup at any time and the general rule is for a 100Litre fish tub you can grow 200 Litre grow tub worth of plants.
Aquaponics is becoming more and more popular and many countries have designed and built aquaponic systems on huge scales and even many people especially in australia have built large systems in there backyards with up to a thousand fish in there tanks. This is a very fun project to undertake but will require a good knowledge of hardware and plumbing.
I'm am currently in the middle of building a bigger aquaponics system with a 5000 litre pond so I may post a new hub on that system later on
Thanks for reading and I hope if you've got some spare time you will give it a go its well worth the effort:).
I also hope I didn't leave anything out ,i always feel like I have let me know if you think there is something missing. goodluck everyone