Before attempting to build any project you first must understand what it is you are trying to accomplish, the principle operating system and procedures and how to tie it all together for a successful, functioning project. Before learning how to build an Aquaponics system, we first must know what it actually is and how it functions.
Aquaponics is not a new technology as evidence of ancient Aztecs using a similar system was discovered long ago. Aquaponics also is not one system, but rather a combination of aquaculture, the growing of fish and other aquatic animals, and hydroponics, the growing of plants without soil, which utilizes a symbiotic combination which feeds the plants fish waste, and in return the fish receive clean water. The benefits of this system is enormous as it allows the growth of an incredible amount of food in a very small area.
How does the system work?
Simply put, Aquaponics recirculates water from a fish tank through a vegetable grow bed. Nutrient-rich fish waste feeds the plants, the plants by removing all the waste, provides clean water returning to the fish which keep them healthy. A classic Win-Win situation. The modern systems are technologically advanced from the primitive original, but works essentially identical in theory and practice. There are numerous different styles and designs of grow beds, the two most common are flood and drain and floating raft style,which the Aztecs used.
Sampling of benefits:
1.The driving benefit of Aquaponics is the ability to grow consumable fish and plants in one system.
2. The system uses about 1/10th the water required to grow plants in the ground.
3. Products grow at a faster rate producing greater yields.
4. Relatively low energy usage.
5. No need to weed or tilling of soil-based plants.
6. Protects against soil borne diseases.
7. Plants are naturally fertilized by the fish waste.
8. Eliminates any dangers of pesticide or chemical contamination.
9. There is no waste water runoff, contamination or erosion.
10. Fish are a critical protein source.
11. Gardening chores are virtually eliminated saving time and backaches.
12. The system can be placed anywhere, outside, in a greenhouse, in the basement if combined with a grow light.
13. It can sized from a windowsill herb garden to a full blown commercial farm.
14. Once the system is setup and running maintenance is very limited, as you’ll have to monitor PH levels, top off water from evaporation and feed the fish.
Samples of Common Varieties of plants grown:
Nearly all types of lettuce
Nearly all types of herbs
What types of fish can be grown:
How to Build an Aquaponics System: Let’s build a typical small type Aquaponics system. Bear in mind this is only a hypothetical model … you can modify the size to fit your desired goal.
A fish tank. For this example a 5-20 gallon glass or plastic tank. The standard sized fish aquarium tank is 10 and 20 gallons and are reasonably priced. As a rule of thumb, you can support 1-2 square feet of growing area for every 10 gallons of fish tank.
Gravel. You’ll need @ 2.5 lbs. Of gravel for every 5 gallons of water. The gravel is for covering the bottom of the fish tank, which will serve as a home to the nitrifying bacteria that converts ammonia to nitrite and then to nitrate, from the fish waste, in order to feed the plants. Pet stores carry natural or colored aquarium pebbles, which are @ 1/8th inch in size. No matter what type of gravel used, be sure to thoroughly wash because any dust will cloud the tank.
Water pump. 3-4 watt pump with the capacity of lifting water 18” to 54” in height at 100 gallons per hour. A small fountain pump is ideal. The pump is used to pump water through the tubing from the fish tank to the grow bed, where after the plants absorb the waste, gravity takes the cleaned water back to the fish tank.
3 feet of plastic tubing sized for pump outlet.
Aquarium air pump sized for the gallon capacity of tank. The air pump is required to blow air into the tank, which is required by both the fish and plants, through the tubing which is connected to the air stone. The air stone breaks the large bubbles created by the pump into micro-bubbles which greatly enhance the oxygenation of the water.
Air stone – 1” to 3”
3 feet of air tubing to connect air pump to air stone, sized for air pump outlet
Grow Bed: Sits on top of fish tank and should be 3” to 8” deep. The grow bed sits on top of the tank and must be slightly larger both in width and length. The bed is filled with a growing medium that the plants grow in. A plastic Rubbermaid container that sits on top of the tank will suffice as long as it’s 3′ to 8” deep.
Growing Medium: Ample supply of pea gravel. Perlite, coconut coir, expanded clay pebbles or peat moss to completely fill the grow bed. A growing medium is a porous, chemically treated inert material that holds the plant roots and maintains moisture.
PH test kit and PH+ and PH- chemical
Fish and Plants to be grown.
Suggested Tools Required:
Electric drill with 1/4”. 3/16th and 1/2” drill bits
Screw Driver(s) … flat & Phillips
Step 1 – Thoroughly wash the gravel several times insuring there is no residual dust, then spread over the entire bottom of the fish tank.
Step 2 – Drill 1/8th inch or 3/16th inch holes (your choice) in the bottom of the grow bed, spaced every 2 square inches for the water to be able to drain back into the tank. Drill a 1/2” hole in a corner for the tubing from the water pump to pass through.
Step 3 – Place the water pump in the fish tank, reset the grow bed on top of the tank, feed the air tube through the 1/2” hole. Leave enough tubing to wrap it along the entire inside of the grow bed. Before feeding the tubing through the hole, drill or punch a small hole every 2 inches to allow water to drip out of.
Step 4 – Fill the grow bed with growing medium, enough to bury the tubing.
Step 5 – Once you fill the tank with water, plug the pump into the electrical outlet to ensure water is being pumped into the grow bed and results in a continuous flow of water back into the fish tank. You may have to adjust the flow on the pump to get the desired water flow.
Step 6 – Connect the air pump tubing to the air stone, place it in the bottom of the fish tank and plug it in. There should be a steady stream of bubbles rising through the water providing plenty of fresh oxygen.
Step 7 – Check the pH level of the water with the PH test kit. Adjust if necessary. The ideal pH is 7, which is neutral. Below 7 and the water becomes acidic, above 7 and the water becomes caustic, both bad for fish and plants.
Step 8 – Allow the entire system to operate without plants and fish for 24 hours to ensure all the chlorine has dissipated. Should you want to add fish sooner, add a chlorine remover, available at pet stores, first.
Step 9 – I recommend adding only half the fish you anticipate raising until the system has about a month to establish itself. Then add the remaining number.
Step 10 – It will require some time for fish waste to collect, therefore it’s best to wait 4 weeks before planting. However, if you can’t wait plant a few seeds or sparsely spaced plants, adding more later.
Aquarium Heater – Should you decide not to raise fish to eat, but rather for the enjoyment of watching them, you’ll most likely choose tropical fish, and they require warm water of at least 78 degrees F. (25.5 C). In order to accomplish this you will need an aquarium heater, which come in either tank-side mount or submerged styles.
Tank Light – Most aquariums come equipped with a florescent light to enable viewing. If yours doesn’t you can add one, but it’s not necessary.
Grow Light – If your system is set up in a low light area it may be necessary to introduce artificial light by utilizing a growth light. Be mindful that direct bright light encourages algae growth which is not good. Be sure not to aim the bulb directly at the tank, but rather above and indirectly at the system. Should you not be able to control the growth of algae introduce a plecostomus, a fish which thrives on eating algae. Depending on tank size and growth rate, you make need more than 1 of these fish.