Duckweed – The Food of the Future

Duckweed  – The Food of the Future 
– by Colle and Phyllis Davis

Portable FarmsDuckweed MAY be the food of the future. Grown under ideal conditions, duckweed ranges between 25% and 45% protein and doubles its growth every 36 hours, and OUR TILAPIA love to eat it.

We do not profess to be experts at growing farm-raised duckweed to feed our fish. In fact, quite the opposite is true. We have grown duckweed in kiddy-pools, large and small containers and even open-air tanks off-and-on for many years and we have not always been successful in our efforts to maintain our duckweed farms, but we keep trying and we continue to experiment to find the answers to pass along to you.

Duckweed seems to overgrow in places that people do not want it to grow – like ponds, rivers and lakes, but it’s been difficult for us to raise it in tubs for more than a few weeks before it dies. If duckweed covers the surface of a body of water, there is an oxygen depletion which kills fish in the ponds, rivers or lakes. (Feed tilapia only enough for them to eat. The remnants are picked off over time.)

Our latest experiments for growing duckweed suggests putting PVC pipes or PVC fittings in the water in the tanks for the duckweed to grow around it (which makes sense) so we’re going to try that and we’ll keep you posted.

If you plan to raise enough farm-raised duckweed to feed your fish for a commercial sized-farm, we recommend you speak with a local botanist in your area that might be able to guide you better than we can. There is a vast amount of scientific research and available information on the Internet about duckweed.

Image of duckweed growing near a bridge. If you look for areas near your own home with standing water, you may see your own ‘starter batch’ of duckweed. 

Fun fact: People asked us for a long time what duckweed tasted like. One day our construction engineer said, “Well, I guess you ought to taste it so you can tell them.” So I did. It tastes like watercress. Tangy, peppery and very clean tasting.  “Thought you’d like to know.” – Colle

Also, starch that comes from duckweed can quickly be changed into ethanol, which it can used instead of corn for ethanol. Farmers from large-scale hog farms, rid their waste through large duckweed lagoons.” It helps manage their animal wastes through biological treatment and can even ‘clean’ hog-waste water and makes the water potable by running the water through enough duckweed. Interesting, eh?

Here are a few links for you to study duckweed and its benefits and complexities:

Portable FarmsDuckweed in kids 8′ kiddy pools

In fact, here is a link to a technical working paper by researchers for the World Bank, Duckweed Aquaculture, A New Aquatic Farming System for Developing Countries, by Paul Skillicorn, William Spira and William Journey – Emena Technical Department, Agricultural Division.

Advice for ridding unwanted duckweed from ponds from the Royal Horticultural Society in London:

Non-chemical controls: Complete control is impossible and growth should be controlled before it reaches nuisance levels. Try the following for control and prevention of duckweed:

  • On small ponds repeated raking or netting will keep the weed under control. Continuous removal is usually necessary
  • On larger pools use a floating boom to sweep from end to end. Sweep at intervals from early in the season and continue until winter dormancy
  • You can compost the removed weed
  • Fit stop-boards at any upstream inlets to prevent duckweeds entering ponds or lakes
  • Weed-eating water birds, such as domestic and ornamental ducks, moorhens and coots will provide some degree of control
  • Grass carp will eat Lemna species
  • Shading can reduce duckweed growth. This can be achieved by planting on the south side of the pond. Waterlilies and other plants with floating leaves can also substantially reduce the level of duckweed. The use of a fountain to disturb the surface may also help

Vertical Growing in Aquaponics

Vertical Growing in Aquaponics
– by Colle and Phyllis Davis


Every inch of space in an aquaponics tray is high-value ‘real estate’ for growing food. Unlike ‘dirt gardens,’ there’s no room for plants to spread their luscious leaves, vines and blossoms across a large area as they mature to produce food.

The rule of thumb (make that a GREEN thumb) is for food to grow as quickly as possible. In other words: Plant it, grow it, harvest it and then repeat the process immediately by planting a new plant that was grown from seed (over a few days) on the SAME DAY the previous plant was harvested, so there is always a continuous cycle of production, and there are always plants in various stages of growth within the farm.

The two years PFAS LLC spent in our Research Center in the Tropics highlighted the problems created from the constant heat and high humidity which forced us to find solutions to this ongoing problems for creating ample air flow, suspension of the plants for vertical growing and allowing for adequate sunshine within the greenhouse. By continual experimentation with locally available materials, we invented a simple trellis system using chicken wire (made of wire or plastic) with 2″ openings and clothes-line rope which solved all our problems. It was very inexpensive and easy to install. THE PLANTS LOVED IT. Their blossoms stayed dry. The new system took the pressure of the stems and vines and allowed for sunshine to reach all parts of the plant and happily, our production soared. When the plants were small, they did require a minimal amount of tying (to the clothes line rope) and then they did the rest on their own! Some of the larger stems require us to delicately thread them through the chicken wire so they would grow naturally.

After 30 days of plant growth (green beans) with the Portable Farms Trellis’ System

After 45 days of plant growth (green beans) with a Portable Farms Trellis.

Two frames containing plastic chicken wire suspeded above grow trays to support growing blooming plants.

Tie soft clothes line rope on top wire from top tray to support growing plants for vertical growing.

The Portable Farms tropical trellis system is yours to copy, modify and use in your own backyard ‘dirt farm,’ your backyard aquaponics system or your commercial aquaponics installation. It’s our gift to you. Now go grow food and send us pictures.


Basil is a High-Value Crop for Aquaponics

Phyllis Davis harvesting fresh delicious basil
from Portable Farms Aquaponics System

Basil – A High-Value Crop for Aquaponics
by Colle and Phyllis Davis

Basil is enjoyed as a fresh-leaf herb on meats and vegetables, prepared in sauces such as pesto, or dried and used in many recipes in cultures throughout the world. Basil grows well in aquaponics systems because of the ideal growing conditions created with warm water and ample sunlight.

When basil is grown in traditional in-ground growing, it is a ‘summer crop,’ but when grown year round in aquaponics systems, it is considered a ‘high value crop,’ especially when sold locally in cold climates when basil would normally be normally be considered ‘out of season.’

Basil growing in a  Portable Farms® Aquaponics System. These plants are 24″ tall and were grown in 55 days. Pesto anyone? Read on . . . 

  • The normal pH of the water in Portable Farms® Aquaponics Systems ranges from 6.5 to 7.2 for ideal growing.
  • Basil enjoys a very wide pH range between 5.1 (strongly acidic) and 8.5 (alkaline) with a preferred range of 5.5 (strongly acidic) to 6.5 (mildly acidic).
  • The roots of herbs enjoy being well-drained between watering cycles.
  • Portable Farms® Aquaponics Systems allow for full sun or the option of grow lights so herbs and vegetables can be grown year round which is ‘out of season’ in many areas and owners may collect top dollar for crops from local customers.
  • Basil seeds grow well in rockwool or Oasis Horticubes.
  • Basil plants may be placed on 8 inch centers and planted off-set in each row within a grow tray allowing for ample room for lush growth for each plant.
  • The root systems for basil do not spread out and are not complex root systems which makes for consistent and easy water flow throughout the grow bed during watering cycles.
  • The basil plant usually grows to a height of 18 to 24 inches and produces many offshoots for harvest per plant.

You can cut back basil two-thirds of the entire basil plant twice before replanting the basil to begin the process again. This extends the harvest of the basil leaves and provides more cash-value crops instead of a one-time ‘grow and harvest cycle’ like lettuce. Basil can also be raised in batches and sold to customers as entire plants.

  • Since one plant will produce for four months (after a two-month initial growth), you would only replant new basil plants every six months and be continually harvesting during each four-month harvest cycle.
  • Each 40′ tray will grow 450 basil plants (on 8″ centers) which allows for 900 basil plants per year grown in a single tray. These 900 plants allow two cuttings each which can be sold to local consumers at wholesale or retail prices in your area.

Bonus – Pesto Recipe We Use When We Harvest our own Fresh Basil

We cannot count times the many times we’ve invited friends to sit with us to enjoy an entire meal of fresh pesto sauce made from our own basil that was spread thick on hot homemade whole-wheat bread and served with sliced, freshly-harvested tomatoes from our own vines in our Portable Farms® Aquaponics Systems. It’s a real pleasure to share healthy and simple food with friends. This is our definition of ‘the good life.’

Portable Farms® Pesto Sauce – Fresh off the Vine

This recipe makes about 2 cups. If you plan to freeze the excess pesto, avoid adding the crushed garlic to the recipe and wait to add it until you thaw and serve the pesto because the garlic can taste bitter after freezing.

Ingredients List:

  • 8 cups fresh basil leaves, torn off vine (discard the stem/vine)
  • 1 cup freshly grated Parmesan cheese from a deli or fine store (don’t use the powdered Parmesan you shake out a canister for pasta)
  • 3 cups of pine nuts – slightly oiled and then toasted brown in an oven for 20 or 25 minutes
  • 3 garlic cloves, crushed
  • ¾ to 1 cup extra-virgin olive oil (depending on how thick you like your pesto sauce). If you plan to freeze your pesto for later use, do NOT add olive oil until you defrost.
  • 1 teaspoon sea salt
  • ½ teaspoon fresh black pepper


  • Place basil, ½ of oil, cheese, pine nuts, and garlic in a food processor. Pulse several times, until well chopped.
  • With machine running, quickly add olive oil in a steady stream, allowing pesto to mix blend and become cohesive but don’t over blend. Process until desired consistency is reached, season with salt and pepper, and serve. Again, if you plan to freeze your pesto for later use, do NOT add olive oil until you defrost.

Feeding a Family of Five with a Portable Farm in 125 sq ft

Feeding  a Family of Five with a Portable Farm in 125 sq ft
by Colle and Phyllis Davis

How much food does a family of five consume in a year?

Starting with USDA data for a healthy diet and accepting that most carbohydrates will come from grains and root crops, the table vegetables for one person can be grown in 25 sq ft of aquaponics grow tray space. So a family of five will need 125 square feet of grow tray space or a Grow Tray 5′ wide by 25′ long.

A climatically adapted greenhouse that is 10′ by 30′ will feed the family of five year-round, forever. That space is only slightly larger than a modern living room. Some of the protein source for the family will come from the fish that are grown in the Fish Tanks of the Portable Farm and the settling tank waste can be used to grow other crops and fruits outside the structure. Plants love the nutrient-laden settling tank waste water and reward the Portable Farmer with exceptional crops yields. The waste water can also be added to compost to speed up the process.

The average family of five consumes one head of lettuce per day for salads, garnish or sandwiches. The lettuce is planted on 8-inch centers in the Grow Tray. The lettuce needs approximately 30 to 40 days from ‘planting to harvesting’ which means there will be 40 lettuce plants in the Grow Tray at all times. 40 lettuce plants require 27 square ft of grow space. Each time a lettuce plant is harvested, a new seedling is placed in the same space to be ready to harvest in 40 days.

What other favorite vegetables are enjoyed by your family? Zucchini, any variety of peppers, eggplant, basil, Swiss chard, kale, cucumbers or maybe you would like a little space beans or bok choy. Find the spacing needed on the seed packet and begin planning out ways to fill up the rest of the Grow Tray.

With 90 square feet to fill up, the space that is 5′ wide and 18′ long will be beckoning to you even in your sleep.

Here is the trick that is the hardest for new Portable Farmers to grasp: THINK AHEAD AND PLAN LIKE A FARMER! Refrain from planting all of the space at once.  That is 27 square feet of open space for lettuce will tempt you to fill it up. Don’t do it. Plant a new baby lettuce plant every day into the gravel. Yes, it will be incredibly hard to do until the entire Grow Tray is finally full and you can stop buying vegetables at the store. It will happen, be patient and know that you are doing the best possible planning for your family’s survival.

Smokers Trasmit Virus in Portable Farms

Tobacco Mosaic Virus
– by Colle and Phyllis Davis

Tomato mosaic virus cause yellowing and stunting of tomato plants and cuts yield production.

tobacco virus leaf

The effects of tobacco mosaic virus on a tomato plant.

Tobacco Mosaic Virus

Tobacco Mosaic Virus




All forms of tobacco, smoke, vapor or nicotine will cause Tobacco Mosaic Virus, Cucumber Mosaic Virus and other blooming plant viruses. 

No marijuana smoking or marijuana smokers should be allowed in the greenhouse.

Smokeless tobacco (chewing tobacco, dip, snuff, pouches) can also carry the tobacco mosaic virus and is transmitted by human hands to the plant material.

Since you cannot use any type of insecticide in an aquaponics system (or you’ll kill the fish), you must protect your plants and fish from toxins, pathogens, and insects.

We recommend that anyone who touches the gravel or the plants wear clean disposable gloves, every time they work in the farm. We also recommend that NO TOBACCO USERS, NO SMOKING AND NO SMOKERS ever be allowed to handle the gravel or handle the plants (with our without gloves) for fear of introducing the tobacco mosaic virus into the farm. We also recommend all plants are grown from seed because small plants brought in from nurseries hold a high possibility for having been handled by smokers and may also contain aphids and other pests.

This Tobacco Mosaic Virus attacks tomatoes, cucumbers and peppers and produces
bumps on the leaves, uneven coloring and stunted and distorted fruit.

Here are some links for more information:




Our Aquaponic’s Course is Fun and Easy – JOIN THE PORTABLE FARMS® FAMILY

Our Aquaponic’s Course is Fast, Fun, and Easy – JOIN THE PORTABLE FARMS® FAMILY

Feed 2 or 200 

The more Grow Tables you build, the more food you can grow and the more people you can feed.

Portable Farms® Aquaponics Systems

A small back yard Portable Farms® Aquaponics System.

A small back yard Portable Farms Aquaponics System.

Aquaponics is easier and more productive than organic gardening or traditional agriculture and uses 95% less water. Portable Farms® Aquaponics Systems also use less electricity and less labor than any other aquaponics system in the world.

To view photos of food commonly grow in Portable Farms® Aquaponics Systems: 

If you’re interested in owning your own aquaponics system, your first goal is to select the size aquaponics system you’d like to operate for your own unique purposes. We always suggest to our customers that they learn how to successfully operate an aquaponics system and if it fits their needs THEN expand to multiple aquaponics modules (the sky’s the limit).

There are literally thousands of websites that can show you how to set up a small workable open-source backyard hobby aquaponics systems without paying for the information. For those who are not able to purchase our systems, we suggest you START TODAY by working with online/open source information so you can learn about aquaponics and build your own farm. We also suggest you visit online aquaponics forums so you can ask questions you may have from other aquaponics enthusiasts. 

Take our email-correspondence course. It's fun. It's easy. It's GREAT information.

Take our email-correspondence course. It’s fun. It’s easy. It’s GREAT information.

Would you like a few aquaponics modules (each module feeds 8 people) so you can begin to sell the food you grow and then expand? If so, then take the Portable Farms® Aquaponics Systems Course© and learn  everything there is to know about aquaponics and begin to build modules.

Or, are you interested in the commercial side of aquaponics that raises and sells vegetables and fish to local markets in your area? You can begin at the top and install multi-acre commercial systems by taking the Portable Farms® Aquaponics Systems Course©.

The future of food production involves growing food in a controlled-environment greenhouse. By growing food in greenhouses, growers are no longer dependent on weather conditions (think climate change), and they can grow food year round, in any climate, and the grower doesn’t need to use harsh chemicals or pesticides to protect their plants.

A completed Portable Farms® Aquaponics System before the plants or the fish have been installed.

A completed Portable Farms® Aquaponics System before the seedlings or the small fish have been installed.

40 days after the fish and plants have been installed in a Portable Farms® Aquaponics System.

40 days after the seedlings and the small fish have been installed in a Portable Farms® Aquaponics System.

farm 8 18 2012

The next step up is almost too easy; yes, you can sell the food you grow. The desire to ‘sell the excess’ is almost too good to pass up. Your neighbors and friends will be delighted to receive your excess bounty for free and a few of them will offer to pay for it. TAKE THE MONEY. It is your reward for being smart and focused on your business. Building a larger installation to house two or more Portable Farms® Aquaponics Systems’ Modules makes the adventure into a real commercial aquaponics business. Starting with about twice as much money as noted above, a person can become a millionaire is less than ten years.

  To view photos of food commonly grow in Portable Farms® Aquaponics Systems:  CLICK HERE.

Cucumbers Are BIG MONEY When Grown in Portable Farms

Portable Farm Cucumbers Harvested February 9, 2012

Harvested cucumbers from a Portable Farm.

Cucumbers Are BIG MONEY When Grown in Portable Farms®
by Colle and Phyllis Davis

Cucumbers are delicious in salads, as a side dish garnished with vinegar and spices, as part of a refreshing addition to a relish tray or even sliced and served on a sandwich!

The cucumber has long been known as a summer ‘fruit.’ Yes, the cucumber is considered a fruit but used as a vegetable. When cucumbers are grown in a Portable Farms Aquaponics System, they can be grown YEAR ROUND and sold to local customers as organic food for top prices. In fact, (this surprised us as well) cucumbers grown in our Portable Farms are a better cash crop than even basil!

Since cucumbers are ‘blooming’ plants, they require:

— Warm temperatures in the greenhouse ranging from 70 to 95 degrees F

— Six to seven hour of direct light per day and LED or fluorescent grow lights from September to April (Northern Hemisphere) for another five hours per day. If direct sun is unavailable, the grow lights must be utilized 18 hours per day. 

— Adequate circulation to assure the blossoms set.

If cucumbers grown in a Portable Farms® Aquaponics Systems are raised and sold as ‘locally grown and pesticide free,’ the grower can receive higher prices further reducing the ROI than stated in this article.

Cucumber production begins 60 to 70 days after seeding.  For good production, a temperature range of 75 degrees to 80 degrees F during the day is desirable.  While peak daytime temperatures of 85 degrees to 95 degrees F are tolerable, prolonged periods of high temperatures may adversely affect fruit quality.  Night temperatures no lower than 65 degrees F will allow a rapid growth rate and earliest fruit production.  At 55 degrees to 60 degrees F, savings in fuel costs will be significant, but growth rate will be slower and harvest will be delayed.

This is a simple diagram of a Portable Farms Aquaponics System

This is a simple diagram of one module a Portable Farms Aquaponics System

Fruit generally grows to market maturity 12 to 15 days after the flower opens.

Considering these variables, yields range from 1 – 1 ½ to 3 pounds of fruit per plant per week, during mid-harvest on an umbrella trained crop.  Twenty to twenty-five fruit may be expected over a 10 to 12 week harvest period.


Cucumber production from a single full size 5′ x 40′ (200sq ft) [1.5m x 12m (18m2) Grow Tray:

  • Each Grow Tray can hold 106 plants 18in x 12in (45cm x 30cm) centers and are planted twice a year
  • Production is normally over a 10 to 12 week period
  • Because the plants spread out so much they need to be trained in a V shape or directly vertical
  • Plants may require some pruning
  • The staking or trellising can be installed permanently
  • Cucumbers yield is between 1.5 and 3 lbs [0.7 and 1.3k] per plant per week depending on variety
  • Yield per plant is 20 to 25 cucumbers per plant depending on variety
  • No pesticides, fungicides or artificial fertilizers are ever used
  • Cucumbers can be harvested and used the same day for peak flavor and texture plus they store well
  • Yields 4,000 lbs to 4,500 lbs [1,800 to 2045kg] per year per Grow Tray
  • 85lbs [38kg] per week
  • 11.7lbs [5kg] per day

Colle Davis, Inventor, with fresh cucumbers from Portable Farms

Each Module contains one Grow Tray, one Fish Tank and one Clarifier. The components to make the Module functional also include a special pump and valve system, a control panel, air pumps and related hardware and wiring.

Labor costs are higher than with lettuce because of the training and harvesting of cucumbers. This is true for tomatoes, zucchini, peppers and any plant that requires extra time after planting. Lettuces does not, plant it and then a few weeks later harvest it and plant the same place again. Two people can operate a 10,000 sq ft PFAS if they are only growing lettuce. With other bush or vine crops two to four additional personnel are required.

Make Money with Your Own Aquaponics’ Business

Make Money with Your Own Aquaponics’ Business
– by Colle and Phyllis Davis

Portable Farms® Aquaponics Systems

Aquaponics is easier and more productive than organic gardening or traditional agriculture and uses 95% less water. Portable Farms® Aquaponics Systems also use less electricity and less labor than any other aquaponics system in the world.

Start somewhere, at some level, now. Modern aquaponics is a brand new field because it encompasses recent technology and innovation along with successful techniques from the past. Aquaponics is evolving rapidly and slowly becoming main stream. The commercial side of aquaponics may take another ten or twenty years to accept on par with hydroponics, but it will happen.

It is the hobbyist, gardener, cook and home owner who are leading the charge on this ‘new’ technology, not the big companies, governments or NGO’s. Aquaponics is up close and personal as only eating can be and it is the opportunity to eat the best food on earth, every day, for a long as you live.

The important part is to get started NOW. Have fun, make mistakes and eat great food.

Another benefit of the Portable Farms® Aquaponics Systems is their wide range of temperature tolerance. Space at the Grow Table level needs to stay in the range of 45 to 104° F (6 to 40° C). The Fish Tank is heated to a constant temperature and helps maintain the temperature inside through the timing of the water cycles. ­

Heating the space can be as simple as adding a small space heater that is placed on the floor. It can be electrical, propane, city gas or even fuel oil powered. Exhaust from combustion needs to be vented as in living space. There are installations measuring 20’ x 36’ (6 x 11m) in Minnesota that only require a small thermostatically controlled electrical heater to keep the space above 45 degrees. There are larger installations in Wisconsin, Oregon and New York heated with wood-burning stoves. These stoves are a lot more work, but work they do in producing great vegetables.

Aquaponics is an ideal business opportunity for young adults, men, women, those currently employed full time or part time, older adults, retired people, and those with disabilities. This is NOT a get-rich-scheme; it requires dedication, start-up capital and a sense of humor to grow any entrepreneurial venture to success. 

Portable Farms® customers say to us almost every day, “I want to start small with a backyard farm and then grow into a larger system, maybe even to a larger size commercial aquaponics operation fairly quickly. Can I do this using your system?”

QUESTION: Can a person or family or small group start really small (for example, one single Portable Farms Module in a greenhouse) and then grow into a commercial success in a reasonable amount of time?

ANSWER: ABSOLUTELY, YES! Let us teach you what we know.


Launching your own aquaponics business involves leveraging the most efficient aquaponics system in the world into a money-making business plan for personal wealth and security. PLEASE NOTE: aquaponics is NOT a get-rich-quick plan for creating wealth. In fact, it requires a capital outlay and the return on investment is dependent on your ability to grow, market and SELL the food you raise. Growing vegetables and fish is the easy part.
There are several distinct steps for making a nice living with aquaponics and maybe even becoming wealthy after a few years of focus and hard work. The best part is that the Portable Farms® Aquaponics Systems installations are doing most of the work with the owner planting, harvesting and selling their healthy food to eager markets.

Launching your own aquaponics business involves leveraging the most efficient aquaponics system in the world into a money-making  business plan for personal wealth and security.

There are several distinct steps for making a nice living with aquaponics and maybe even becoming wealthy after a few years of focus and hard work. The best part is that the Portable Farms® Aquaponics Systems installations are doing most of the work with the owner planting, harvesting and selling their healthy food to eager markets.

Cost of An Aquaponics System and Operating Tasks

Cost of An Aquaponics System and Operating Tasks
by Colle and Phyllis Davis


The majority of daily tasks include planting, harvesting and feeding the fish. Repeat the next day.

aug 20 interior2There are two assumptions that will be made here regarding the operations for a backyard aquaponics system:

1) your installation is, or is similar to, a Portable Farms® Aquaponics System.

2) You have built a medium/media based (not a raft based) aquaponics system. Operations include the steps that are necessary for you to keep the fish and plants alive and healthy.

A backyard farm that feeds 8 people generally takes about ten to fifteen minutes per day to maintain. This includes feeding the fish, planting seedlings and harvesting. Operations are NOT time consuming but they are DAILY operations that cannot and should NOT be skipped.

When you’re dealing with living aquatic animals, they require daily care, attention and yes, even affection to remain healthy and grow to their full size. If your fish are ‘stressed’ for any reason, they won’t eat – – – – and if they don’t eat – – – – they don’t poop – – – – and if they don’t poop, your plants will not be healthy.  So, if you’re going to be gone for longer than a day or so, ask a friend or neighbor (that you trust) that will take care of your aquaponics system.

Here’s the full cost breakdown of a backyard aquaponics system: READ ON . . . 

  • Greenhouse: Must be able to keep the interior temperature between 40 and 104° F. The costs are dependent on your choice of design
  • Wooden or concrete floor/slab – from $100 to $300
  • Insulated stem wall to set the greenhouse on top of for more height – 2×4’s and plywood – $250 to $350
  • Fish tank – sometimes known of as a livestock watering trough  – $150
  • Lumber for the Grow Tray – 2×4’s, 2×6’s, plywood, etc – between $800 and $1,200
  • PVC pipe and fittings  – $100
  • Misc – $250

You may even have some of the materials on hand or have access to recycled materials at a reduced cost. Even if you have to pay full retail price for everything, an operating aquaponics farm is a fantastically good deal. Plus, a Portable Farms® Aquaponics System is infinitely expandable because of it modular design. You can expand it and begin selling the excess to create a small income.

tilapia Oreochromis mossambicusOperational tasks include:

1. Maintaining adequate levels of water in the fish tank at all times
2. Feeding your fish a high protein fish feed each day (singing to your fish is optional but they do enjoy human contact and they do enjoy the sound of talking and singing)
3. Always wear disposable gloves when preforming tasks in the building
4. Keeping the pH balanced in the fish tank
5. Stocking the appropriate number of fish in the fish tank that is in balance with the area of the grow tray

6. 24/7 aeration provided for the fish at all times (bubbles).

Cheap Aquaponics “Startup Fish”

Cheap Aquaponics “Startup Fish”
– by Colle and Phyllis Davis

“Can we use goldfish or crayfish or something besides tilapia in our backyard aquaponics system?”

gowithflowThis is a frequently asked question and prompted a conversation with a new ‘aquaponist’ at my local Home Depot store which has prompted me to make a list of the fish that can be used in aquaponics for new aquaponics farmers to get started with because of choice or local regulations or restrictions.

The gentleman in the plumbing section of Home Depot had to help me find a component we use to manufacture the PFAS Kits and he asked me what I was using so many, I told him they were used in our manufacturing process. He said, (you will not believe this), ‘Oh, are you doing aquaponics?’

I nearly fell down from surprise. He explained that he had a small aquaponics system in his backyard and was using goldfish poop to raise the most amazing basil and peppers he had ever seen. It’s a small world to meet someone with an aquaponics system that actually guessed what I was building. His explanation was that another fellow builds hydroponic systems for people and uses the same item in a very different way. But back on topic. . .

The list of aquatic animals below includes enough species so you can get started today with a tiny aquaponics system to learn and grow with to see how amazing the technology really is at growing vegetables and fish. My original setup was a dishpan with aquarium gravel laid across an aquarium. The fish happened to be tilapia because it was my job at UC Davis (back in the early 1970’s) to clean the fish tanks, a nasty smelly job.

Each species has different requirements and are more or less hardy and easy to maintain. The list below is not all-inclusive, but is meant to be a basis for an inexpensive beginner aquaponics setup so you can get your hands wet.

Species Positive Cost Negative
Goldfish Hardy, readily available, poop a lot Cheap Tough to find a constant market – not for eating
Koi Hardy, readily salable as ornamentals, can be fed cheap dog food, do not have to replace very often Relatively cheap No one eats them, limited market
Catfish Hardy, grow fast, seasonally available, chow is commercially available Relatively cheap Seasonal availability of fry and depressed markets
Carp Really hardy, fast growing, will eat almost anything May be tricky to obtain fry No food market in US
Crayfish/Prawns Can be raised in conjunction with any other fin fish or by themselves. Relatively inexpensive to obtain Most are cannibalistic and must be provided housing (short sections of PVC pipe) to keep any number to harvest size.
Perch New candidate – Feed just becoming available Not cheap Regional markets only
Bass Not recommended because you have to feed them live bait Relatively inexpensive Fish and Wildlife regulations on sale for food










By providing these fish with a clean water supply, aeration and food, you are ensuring a constant supply of the finest poop your system can handle.

Two caveats here:

  1. You will lose fish – this means some of them will die. Get used to it, its farming.
  2. Unless you are using the PFAS, you will have problems with sediment in the gravel so you will have to clean the gravel occasionally. Get used to it, its farming.

With the PFAS the #2 above is not true. Oh, and to use the PFAS you will need to complete the Aquaponics University Portable Farms Aquaponics Systems Course©.