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Day 1: Gathering Materials

Well, after a great deal of scattered research we decided today to start gathering materials for our project.  We decided to use a modified “Ebb and Flow” strategy for our first attempt.  We are dealing with a limited, indoor space in a house that we rent so we’re looking for something compact, clean, efficient, and a good test bed for future expansion.  I’d like to thank bluemist431 and his youtube channel for giving us the inspiration to create our first design.  We are using a hybrid of 2 of his designs to create our system.  Check out bluemist431′s youtube channel here.

Listed here is our preliminary shopping list.  As we’re trying to create much of the system on a budget, we’ll be shopping around on craigslist to pick up some of the larger odds and ends, especially the fish tank and accessories.

  • A tank for the fish: 20-30 gallon, (budget $40)
  • Gravel – 2.5 lbs./gravel for every 5 gallons of water in the fish tank ($20)
  • Water pump – we picked up an Eco264 submersible (pum[s 264 gallons/hour)
  • 20 ft. of plastic tubing that fits the outlet on your water pump ($15)
  • Aquarium air pump – we picked up an Eco Air2 4 watt pump
  • Air stone (1” – 3”) ($1 – $2)
  • Tubing for air pump and air stone ($5)
  • Grow Bed – must sit on top of fish tank and be 3” – 8” deep – we picked a 36″ plastic bin
  • Growing Medium – Expanded clay pebbles (we spent $10 on a good sized bag)
  • pH test kit and, depending on the pH of your water, pH down or pH up ($5 – $15)
  • Fish and plants


Sleep with the fishes…

Do’s and Don’ts of choosing fish for Home Aquaponics

DO:

  1. Let your tank fully cycle (2 weeks should be perfect) before adding fish.
  2. Get your water fully tested both prior to adding fish and on an ongoing basis once the tank is stocked.
  3. Buy your fish from a reputable pet store .
  4. Choose a hardy breed (I am now using comet goldfish – good size and seem to be pretty strong.

DON’T

  1. Forget to rinse your Hydroton prior to adding to grow bed – failure to do so will hurt your fish and make your tank VERY cloudy.
  2. Forget to account for heat loss from grow bed, for a 20 gallon tank you might need a 40 gallon heater.
  3. Buy “feeder fish” on the cheap – these fish are usually packed into tight confines and come with *FREE* diseases.
  4. Pick anything too frilly or pretty – your girlfriend might like them today but she will cry when you flush Nemo in a few days.



 


Back in the Aquaponics Saddle

Ok Folks!  After quite a long hiatus from any blog posts I’m hoping to get the time to keep y’all updated.  First thing’s first… it’s been about  one month since the arrival of all the bits and pieces I used to cobble together my aquaponics setup… and at this point I now have a growing garden, stocked with lettuce, chives, parsley, and basil… ranging from small sprouts to some developing plants.  I’ll have to admit that MUCH has changed since my original plan was published on this site.  I’ll dedicate an entire blog post to the original plan, versus what the final revision worked out to.  The purpose of today’s post is to give a status update for those who are following.

 

 


The Eagle has landed

Ok, so i think we finally have everything we need… here’s what arrived in the last few days:

  • All Ikea Broder parts and pieces – it took two trips to our local Ikea (Stoughton, Mass) but we finally have what we need.  We’ll be working from the shorger (39″) poles since the 7′ wouldn’t fit in the wife’s car… c’est la vie….
  • Fish tank from amazon…. good set, saw just the filter at a pet store for $40 and i bought the whole 20 gallon tank set for $109 delivered.
  • Bulkhead valves from amazon – they have 2 different size attachments which screws me as i ended up with 2 plastic bins instead of the one large i had envisioned.  I’ll have to get a length of 3/4″ tubing for one of the exit valve.
I picked up some seeds for the aquaponic garden today:
  • Boston bibb lettuce (2 kinds, one organic martha stewart brand and one regular – harrvest times were about 15 days difference… we’ll see in reality.
  • A few other lettuce types – will test for optimal strand
  • chives
  • cilantro
  • snow peas (might be tough)
  • basil

 

I’ve run into some issues, here are the big ones…

  1. I bought a whole micro sprinkler head that attaches to the 3/16″ tubing i picked up at Organically Grown Hydroponics in Cranston, RI.  The issue is i can’t convert the 1/2″ submersed pump feed to the 3/16″ tube, seems so simple but having no luck.
  2. I thought the width of the Ikea shelves would be the full width of the shelving unit meaning it would sit perfectly in my window adjacent to my bookshelf and dresser… unfortunately the t-legs for the shelf sit outside the width of the shelf – the total width of the unit is 48″.
  3. I am concerned about the amount of sun the plants will get from inside the window, mmy conisder running the tubes out the window in the summerfor max sun exposur

Day 2: Gathering Materials Continued

Ok, so the quest to gather everything else we need is moving along… as is the price tag.  I had the dreaded wife comment today… “this better work!”… “Ok honey”.  That being said, I think by the coming weekend we’ll be ready to start assembling.  Here’s what I ordered today – (all through Amazon.com with FREE shipping)

In addition, I went to the IKEA site and created a shopping list for the Broder rack and shelving we’re going to use.  I added the following items to the list:

  • 2 Galvinized front brackets
  • 2 4′ posts
  • 2 l-foot brackets with brace
  • 2 broder shelves (max load 220 lbs – crossing my fingers the tank comes in below that….)

 

I also scanned in my sketches from yesterday morning… BEWARE – they are VERY TECHNICAL!


Aquaponics FAQ

What is aquaponics?

Aquaponics is the combination of recirculation aquaculture and hydroponics. In aquaponics, you grow plants and fish together in one integrated system. The fish waste provides a food source for the growing plants and the plants provide a natural filter for the water the fish live in. This creates a sustainable ecosystem where both plants and fish can thrive. Aquaponics is the ideal answer to a fish farmers problem of disposing of nutrient rich water and a hydroponic growers need for nutrient rich water.

Is aquaponics organic?

Aquaponics is a completely natural process which mimics all lakes, ponds, rivers and waterways on earth. The only input to an aquaponic system is fish food. The fish eat the food and excrete waste, which is converted (by beneficial bacteria) to a form that that plants can use. In consuming these nutrients, the plants help to purify the water. You can not use herbicides, pesticides or other harsh chemicals in an aquaponic system, making the fish and plants healthful and safe to eat.

This process could not be more organic but getting a USDA organic certification for a culture system that does not use soil is tricky. A couple of commercial growers in the US have had their plants certified as organic. The USDA has not finalized organic certification standards for fish yet.

What are the benefits of growing Aquaponically?

The combination of aquaculture and hydroponics is quite new and the potential for using aquaponics to grow high quality food around the world is tremendous. Here are some of the many advantages of aquaponic food production:

  • Aquaponics utilizes the nutrient rich water from aquaculture that otherwise would have been a waste product or would need to be filtered in a costly manner.
  • Aquaponics eliminates the cost and time involved with mixing traditional hydroponic nutrients.
  • Aquaponics provides a truly organic, natural form of nutrients for the plants.
  • By eliminating the soil in vegetable production, you eliminate all soil borne disease.
  • Aquaponics uses a fraction of the water that traditional field production does because no water is wasted or consumed by weeds.
  • In aquaponics, plant spacing can be very intensive, allowing you to grow more plants in a given space.
  • With high stocking densities in the fish tank, plants will quickly grow and develop in an aquaponic system.
  • In aquaponics there cannot be any pesticides or herbicides used, making the end product healthier and safer.
  • If your climate permits or if you are growing in a greenhouse, you can grow crops in an aquaponic system year-round.

What plants can I grow?

Early on in the research of recirculating aquaculture systems, experiments were done to determine the efficiency of aquatic plants in consuming the nutrients in aquaculture water, therefore helping to purify the water for the fish in the system. As research continued, terrestrial plants were tested and proven to be an effective means of water purification for aquaculture and this nutrient rich water a nearly ideal hydroponic solution for growing plants.

Lettuce, chives and other leafy crops were first considered for aquaponics but, more recently, commercial growers and researchers have had great success with tomatoes, cucumbers, peppers, melons, flowers and many other crops.

What fish can I raise?

Tilapia, a fresh water that is fast growing and has firm white meat when filleted, is most commonly raised in aquaponics because it is very hardy and can tolerate a wide variety of water quality conditions. Other fish, such as crappie, brim, bass, carp, goldfish and koi can all be raised in aquaponics. If you are considering home food production or commercial aquaponics, you should start by contacting the agency that oversees fish and waterways in your area to find out if there are any restrictions on what fish you can raise.

How many fish can I put in my fish tank?

It depends on the size of the tank and the type of filtration you have. In an aquarium-based system, a good rule of thumb is to stock the tank at 1″ (of fish length) per gallon of water. In larger systems with proper filtration, commercial growers usually stock the tank to a maximum of 1/2 lb of fish/gallon of water.

How many plants can I have with a certain number of fish?

The number of plants you can grow is directly related to:

  1. The number of fish
  2. The size of the fish
  3. The amount of fish food added daily

The scientists at the University of the Virgin Islands have determined that for each 60-100 grams of fish food added per day, you can support 1 sq. meter of plants in raft aquaponics.

Can I make money doing this?

Maybe. Aquaponics, like any business, takes an adequate investment in equipment, proper design and excellent management and marketing skills. Plus, you need to be a skilled fish culturist and plant grower. With those qualifications, an aquaponic farm can be quite profitable.

Commercially, aquaponics is in its infancy but, as the technology develops and is refined, it has the potential to be a more efficient and space saving method of growing fish, vegetables and herbs. By incorporating aquaponics, hydroponic growers can eliminate the cost and labor involved in mixing a fertilizer solution and commercial aquaculturists may be able to drastically reduce the amount of filtration needed in recirculating fish culture. Although there is currently a limited number of commercial aquaponic operations, many people are expressing a strong interest in this intensive method of food production.

I found some old tanks, can I use them for the fish tank?

Your fish tanks and the materials used in your system should be food-grade plastics. This means that they won’t leach chemicals into the water in the system. You should not use any tanks or containers that have had contents other than food or that aren’t recommended for fish or plant culture.

What do I feed the fish?

If your goal is optimum growth rates and food production, you should feed your fish a species-specific, commercially available fish food. There are many manufacturers of fish food. You can search for sources online or through local resources such as feed stores and ag suppliers. If you have a low-tech system and maximum production is not your goal, you can grow or make your own fish food. Duck week, water lettuce, worms and similar live feeds are often fed to tilapia.

How does it work?

The key to a successful aquaponic system is the beneficial bacteria which convert the fish wastes into nutrients that the plant use.

More than 50% of the waste produced by fish is in the form of ammonia, secreted through the gills and in the urine. The remainder of the waste, excreted as fecal matter, undergoes a process called mineralization which occurs when Heterotrophic bacteria consume fish waste, decaying plant matter and uneaten food, converting all three to ammonia & other compounds. In sufficient quantities ammonia is toxic to plants and fish. Nitrifying bacteria, which naturally live in the soil, water and air, convert ammonia first to nitrite and then to nitrate which plants consume. In your aquaponic system the nitrifying bacteria will thrive in the gravel in the fish tanks and in the growing medium in the grow bed. The plants readily uptake the nitrate in the water and, in consuming it, help to keep the water quality safe for the fish.

Do I need a greenhouse?

A greenhouse provides protection from enviromental factors such as heat, cold, wind, rain and insect intrusion. In most climates a greenhouse is required. A greenhouse can even be beneficial in the tropics to protect the crops from rain, wind and insects. The type of greenhouse and the enviromental control equipment varies widely depending on climate. There are aquaponic growers, however, that have hobby systems indoors, in a basement or garage. When indoors, they have to add artificial lighting for the plants.

Can I do this as a hobby or school project?

On a hobby scale, aquaponics is catching on quickly. A home aquarium, with ornamental or food fish, can be combined with a mini garden, growing herbs, vegetables or flowers. A hobby system can serve as a beautiful show piece or a food production system, depending on the size. Many backyard gardeners are setting up systems to grow hundreds of pounds of fish and all the fresh vegetables a family needs. If you are interested in hobby aquaponics or instructions on how to build a system for a science fair project, check out the book Desktop Aquaponics.

In educational applications, aquaponics is an excellent model of natures biological cycles. For educators, we have a comprehensive Aquaponics Curriculum Package, complete with an Educator’s Guide, Student Manual, Transparencies, a CD-Rom and a subscription to the Aquaponics Journal.

The Aquaponics Journal is a bimonthly publication covering aquaponics. Each issue offers interesting, informative features on commercial, hobby, research, and educational applications of aquaponics.

For a thorough overview of aquaponics, we offer the recently released “Introduction to Aquaponics” on VHS Video and DVD.


How Aquaponics Works

How Aquaponics Works

Aquaponics is the ideal answer to a fish farmer’s problem of disposing of nutrient rich water and a hydroponic grower’s need for nutrient rich water. Essentially, aquaponics mimics every natural waterway on earth. It is used to grow food crops in a concentrated, yet sustainable manner.

The main input to an aquaponic system is fish food. The fish eat the food and excrete waste. More than 50% of the waste produced by fish is in the form of ammonia secreted in the urine and, in small quantities, through the gills. The remainder of the waste, excreted as fecal matter, undergoes a process called mineralization which occurs when heterotrophic bacteria consume fish waste, decaying plant matter and un-eaten food, converting all three to ammonia and other compounds. In sufficient quantities ammonia is toxic to plants and fish.

Nitrifying bacteria, which naturally live in the soil, water and air, convert ammonia first to nitrite and then to nitrate which plants consume. In an aquaponic system the heterotrophic and nitrifying bacteria will attach to the tank walls, underside of the rafts, organic matter, the growing medium (if used) and in the water column. The beneficial bacteria discussed here are natural and will inhabit an aquaponic system as soon as ammonia and nitrite are present.

Essentially, you have three crops to keep alive in aquaponcis – the fish, the plants and the beneficial bacteria. These three living entities each rely on the other to live. The bacteria consume the fish waste keeping the water clean for the fish. In the process, the bacteria provide the plants with a usable form of nutrients. In removing these nutrients through plant growth, the plants help to clean the water the fish live in.

Aquaponics is a very efficient method of growing food that uses a minimum of water and space and utilizes waste, resulting in an end product of organic, healthful fish and vegetables. From a nutritional standpoint, aquaponics provides food in the form of both protein (from the fish) and vegetables.


A great Aquaponics design by Nelson Pade – Aquaponics design

Build a Mini-Aquaponic System

A select article from the Aquaponics Journal
by Rebecca Nelson

A mini aquaponics system is an excellent means of demonstrating aquaponic principles and the nitrification cycle in a recirculating aquatic environment. Following are instructions for building a small system that is ideal for a teacher, students of hobbyists who wants to get a start in aquaponics.

What You’ll Need

Following is a list of the parts you’ll need to build an aquaponic system. The next section, Components Explained, describes and explains each of these components and includes recommendations for alternative items and specific products.

  • A tank for the fish: 3-20 gallon, glass or plastic container ($5 – $20)
  • Gravel – 2.5 lbs./gravel for every 5 gallons of water in the fish tank ($2 – $5)
  • Water pump – 3-4 watt pump capable of lifting 18” – 54” at 30 – 100/gal/hour (small circulation or fountain pump is ideal) ($19 – $40)
  • 3 ft. of plastic tubing that fits the outlet on your water pump ($1 – $2)
  • Aquarium air pump sized for the number of gallons in your fish tank ($8 – $16)
  • Air stone (1” – 3”) ($1 – $2)
  • 3 ft. of air tubing to connect the air pump to the air stone (must fit the air pump outlet) ($ 1)
  • Grow Bed – must sit on top of fish tank and be 3” – 8” deep ($ 5 – $20)
  • Growing Medium – enough pea gravel, perlite, coconut coir, expanded clay pebbles or peat moss to fill the grow bed ($2 – $5)
  • pH test kit and, depending on the pH of your water, pH down or pH up ($5 – $15)
  • Fish and plants

Tools Required

  • Drill with 1/4” or 3/16” bit and 1/2” bit
  • Scissors
  • Electrical tape

Component Explanation

A tank for the fish
The fish tank can be a glass or plexi-glass aquarium or you can use any other clean container that holds water, for example, a plastic tub, bucket or barrel. We recommend anything between 3 – 20 gallons, although, you can go with a larger tank if you have the space. Small, clean plastic amphibian cages, available in most pet shops, make an excellent mini-system. They hold about 3 gallons and are quite inexpensive.The standard sized fish aquariums of 10 and 20 gallons are also reasonably priced. The larger the tank, the larger grow bed area you can support. As a general rule, you can support 1 – 2 square feet of growing area for every 10 gallons of fish tank water.

Gravel for tank bottom
The gravel serves as a home to the nitrifying bacteria that convert ammonia to nitrite and then to nitrate, which can be used by the plants. Most pet stores carry natural or colored aquarium gravel. The individual pebbles are about 1/8” in size. Be sure to wash the gravel thoroughly before using it because it is often dusty. Unwashed gravel will cloud your tank water.
Water pump and tubing
A small water pump is used to pump the water from the fish tank to the grow bed. After the water is pumped into the grow bed, it gravity-feeds back to the fish tank. You’ll need enough tubing to go from the outlet on the pump to the top of your grow bed and form a circle within it.
Air pump, air stone and tubing
You need an air pump to blow air into the tank water for both the fish and the plants. Tubing connects the air pump to an air stone at the bottom of the tank. The air stone breaks the stream of bubbles coming from the air pump into micro-bubbles, which greatly increase the oxygenation in the water.
Grow bed
The grow bed, which sits on top of the tank, must be slightly larger than the length and width of the fish tank. The grow bed is filled with a growing medium that the plants grow in. A plastic Rubbermaid container, a garden planter or other container that will sit on top of the tank will work fine. The container should be between 3” – 8” deep.You can use a plastic tub or, for a very nice looking unit, build one out of plexi-glass and seal it with a non-toxic, silicone glue. If you build the grow bed, you can accommodate an aquarium light by making a cavity in the grow bed that the light can slide into. If you are using some other kind of container, a light can sit just behind it if there is room.

Growing medium
A growing medium is a porous, chemically inert material that holds the plant roots and maintains moisture. Examples include: perlite, expanded clay pebbles, peat moss, pea gravel and coconut coir. You need enough to fill your grow bed.
Fish and plants
In an aquaponic system, the fish provide the nutrients the plants need and the plants purify the water by consuming those nutrients.

Optional Components

Aquarium heater (for tropical fish)

Most gardeners or aquarists setting up an aquaponic system choose ornamental fish for the tank and most ornamental fish originate in tropical waters. A tank temperature of 78 degrees F will need to be maintained for tropical fish. Two kinds of aquarium heaters are available, submerged and tank-side mounted. Either will work, but be sure the heater you choose is sized for the number of gallons of water in your fish tank. If the aquaponic system is placed in an area where the air temperature is maintained between 70 – 76 F or, if you choose cool water fish goldfish, you do not need a heater.

Light for fish tank

Most aquariums have a florescent light so you can see the fish and monitor their health. You can add one if you’d like but it is not a necessity.

Grow light for the plants

If you establish your system in an area with low light levels, you may need to add artificial light for healthy plant growth. Keep in mind that bright light will quickly encourage algae growth in the fish tank. You should try to point an artificial light in a way so that it does not directly penetrate the fish tank. If you do have rapid algae growth, you can scrape the interior walls of the fish tank or buy a plecostomus, a fish that eats algae. If the grow bed is in a windowsill with bright sunlight, in a greenhouse or planted with plants requiring low light levels, a grow light isn’t necessary.

Assembly Instructions

Step 1

Thoroughly wash the gravel and place in the bottom of the fish tank.

Step 2

Drill 1/8” or 3/16” holes in the bottom of the grow bed every 2 square inches so the water can drain into the tank. In one of the back corners of the grow bed, drill a 1/2” hole for the tubing from the water pump to pass through.

Step 3

Place the water pump in the fish tank then set the grow bed on top of the tank. Feed the tubing from the water pump through the 1/2” hole. Leave enough tubing to extend about 3/4 the height of the grow bed and to loop around the inside of the grow bed. Cut off any excess tube and fold the end over. Seal the folded piece with electrical tape.

Step 4

Fill the grow bed with the growing medium to just under the top of the tube.

Step 5

Puncture small holes every 2 inches in the section of tubing that loops in the grow bed.

Step 6

Cover the loop of tubing with an inch or two of growing medium.

Step 7

Fill the fish tank with water. Plug in the pump to ensure that the water is pumped into the grow bed, trickles down through the growing medium and continuously back into the tank. Depending on the size of your tank, grow bed and pump, you may have to adjust to flow.

Step 8

Connect you air pump to the air stone with the air tubing. Place the air stone in the tank and plug in the air pump. A steady stream of bubbles should rise through the water, providing fresh air

Step 9

Check the pH of your water using litmus paper, a pH test kit or pH meter. Limtmus paper and inexpensive pH test kits are avilable in most hardware pool supply stores. The ideal pH is 7.0 for an aquaponic system. If it is higher than 7.2 you should lower it with a “pH down” product and if it is lower than 6.8 you should raise it with a “pH up” product, both of which are available from aquarium stores.

Step 10

Allow the unit sit for 24 hours to be sure all chlorine has dissipated from the water. If you want to stock you fish right away, you’ll need to add a chlorine remover, which is available from aquarium shops and pet stores.

Step 11

Add your fish to the fish tank. Initially, you should lightly stock your tank with no more than 1/2” of fish per gallon of water. Once your system has been established for over a month you can increase to fish density to 1” per gallon of water.

Step 12

Ideally you should wait approximately 4 weeks to add plants to your system, but if you are eager to plant it, add just a few plants or seeds and increase plant density in a month or so when your system is well established.

Fish and Plant Selection

In selecting your fish, choose hardy species like goldfish, guppies, angelfish and other common varieties available from your local aquarium or pet store. Most desktop aquaponic gardens do not include food fish because there isn’t enough space to grow them to maturity. If you do want to raise food fish or a local species, be sure to provide adequate water temperature and feed.

A desktop aquaponic garden will support most varieties of house plants, lettuce, spinach and herbs. Ideally, you should start your plants from seed in a grow cube (also called jiffy cubes) or loose in the growing medium in your grow bed. Very small seed can be sprouted by placing them between two paper towels that are kept warm and most. You can also transplant plants from an existing hydroponic system with good results.

If you must transplant from soil, thoroughly wash away all of the dirt surrounding the roots and wash the leaves being sure to remove any pest insects.

You will have the most success with leafy vegetables like lettuce, spinach and herbs or houseplants such as anthodium, dracaena, dieffenbachia and philodendron.

You can also plant aquatic plants in the fish tank. They will provide a more natural habitat for the fish and aid in purifying the water.

Nitrification Cycle

Fish excrete ammonia in their wastes and through their gills. In sufficient quantities ammonia is toxic to plants and fish. Nitrifying bacteria, which naturally live in the soil, water and air, convert ammonia first to nitrite and then to nitrate. In your aquaponic system the nitrifying bacteria will thrive in the gravel in the fish tanks and in the growing medium in the grow bed. Nitrate is used by plants to grow and flourish. The plants readily uptake the nitrate in the water and in consuming it, keep the levels safe for the fish.

System Maintenance

The only daily input in this system is fish food. With any aquarium, frequent small feedings are better than fewer large feedings. Unless you have a really large tank, a pinch of food is all it takes. You should never feed more than the fish can completely consume in 5 minutes. Most tropical fish will be fine with a dry flake fish food but occasionally varying their diet with brine shrimp or blood worms will definitely keep them healthier and happier.

The water level in the tank will slowly decrease as some water is absorbed by the plants and some evaporates. Every few days you should refill the tank to the top. About once a month a 10 – 15% of the tank water should be siphoned out and replaced with fresh water.

Experiment Ideas

An aquaponic system is an excellent tool for experimentation and proving or disproving a hypothesis. Following are four theories and experiments that can be done to prove each.

Theory 1

Although an aquaponics system will produce good plant growth, the hydroponic system with precisely measured nutrients will produce faster growing, higher quality plants.

Experiment 1

Set up a hydroponic system and an aquaponic system. Monitor and document which one best supports plant growth.

Theory 2

A healthy aquaponic system has ample nutrients for leafy crop growth, but fruiting plants will be lacking sufficient quantities of certain elements.

Experiment 2

Plant a leafy crop such as lettuce and a fruiting crop such as tomatoes and monitor to see which one does best in aquaponics.

Theory 3

A pH of 7.0 is the best for an aquaponic system. At a lower pH, nitrification slows down and the water quality will be reduced, stressing the fish, and at a higher pH the plants will be stressed.

Experiment 3

Set up three aquaponic systems. Run each at a different pH, one at 6.0, one at 7.0 and one at 8.0. Observe and document the plant growth and fish health at varying pH levels.

Theory 4

Denser fish populations will support more plant growth due to increased fish waste and nutrients in the water.

Experiment 4

Set up two aquaponic systems, stock one with 1” of fish/gallon of water and the other with 1/2” of fish per gallon of water. Observe the difference in plant growth.


Prep Work: Our favorite aquaponic design

Here is a design we found through Ikea Hacks and Conceptual Designs

As designers we give ideas a form and we transform them into things. We can’t certainly solve the world’s challenges, but what we can do is to create a concrete storytelling about them. A narrative.


Malthus is one of these tales. It is an in-home aquaponics unit designed for the next generation kitchen or living room. It grows one meal a day: a portion of fish and a side salad. Aquaponics farming is a technique that combines the cultivation of fish with the growing of vegetables. The fish provides rich fertilizer for the plants and in return, the plants clean the water from the tank. The fish and the plants co-exist in a symbiotic relationship.

Malthus is an appliance for the kitchen of the future that grows food right next to where you cook it. Malthus consists of a fish tank that holds 400 litres which can support more then 2kg of fish like tilapia, salmon, grey fish or carp. The water is pumped through three cultivated grow beds which filter the water for the fish.

Malthus is designed to optimize space and costs with indoor food production. The weight of the fish tank is comparable to the one of a full bathtub, its width is about the size of two small refrigerators. Its parts are made of elements available in most DIY stores.


Malthus #01 was built thanks to the collaboration of Ola Nilsson and presented for the first time at the 10th edition of NESS – Nordic Environmental Social Sciences Conference – Stockholm 14th -16th June 2011 within the context of the exhibition “Power Landscapes” curated by Po Hangström. The theme of the conference is also the theme of an art project where the invited artists (Katia AglertNew Beauty CouncilCristine Ödlund) presented works on design as a tool for social and environmental engagement.

Malthus has a planned production limited to 100 numbered pieces. The first piece (Malthus #00) is the prototype currently running in our office in Zurich, thanks to Laura Vargalyte, our intern. The design and the production factors of Malthus have been made possible by the technical support of Andreas Graber from UrbanFarmers and Head of the Aquaponics project of the Zurich University of Applied Science who has introduced us to urban farming and to Aquaponics techniques.

A special acknowledgement goes to Stefano Massa for making things run smoothly throughout the project. This text has been kindly edited with the collaboration of Liz Henry Economou of Nuance Words.