“Aquaponics for Sustainable Food Growth: What Foods Can You Grow in Your Own System, and What Should You Expect?”

Aquaponics is a unique way of gardening because virtually every “crop” is different. Most systems are completely custom designs, made with a mix of new and recycled materials. Some are held completely indoors and others are completely outdoors. The lack of soil and the fact that the system is completely self-sustainable mean that it’s incredibly earth friendly, and is a great way of beginning a self-sustainable lifestyle.

The amount of food you can produce using an aquaponics system will vary based on the size of your system. As a general rule of thumb, a tank size of 260 gallons can host between 50-80 fish. This size supports grow beds between 317 – 475 gallons.

Take a look below at the different types of food commonly found in aquaponics systems, and what you can expect when growing them in an Aquaponics System.

Fish

Yes, this is the most obvious, but it’s also worth a few notes of caution. While fish are a large part of your growth system, you shouldn’t expect to feed your family fish more than once or twice per week, or you could offset the balance of your system. The fish serve as a fertilizer for the plants you’ll continue to grow. These plants will need a sustainable and stable pH balance, which means quick changes could cause chaos. However, as long as you are able to maintain your system within the ratio guidelines and without pH changes, by all means, enjoy some delicious fish tacos! Just be sure to monitor your system as you would when removing plants or other materials.

In addition, before planning to add your aquaponic fish to your diet, you’ll want to insure that they are edible, and legal in your area. For example, Tilapia is banned in some areas, due to people raising them and releasing them into waterways, where they are considered a threat to native species. You’ll also want to make sure that the fish you purchase are suitable for your climate, particularly if your system is outdoors. For example, catfish raised in Florida will not survive cold winters, but catfish raised in the northern states will.

It’s also worth noting that if you don’t plan to eat fish at all, but simply use them for your eco-system, you will not have nearly as many concerns. Gold fish, koi and even oscars make beautiful additions to your aquaponics system if you plan to eat vegetarian.

Root vegetables

Many people assume that because Aquaponics systems do not have soil, that root vegetables cannot be grown in them. However, this is not entirely true. As Sylvia Bernstein states in her book, “Aquaponic Gardening,” even carrots and potatoes will grow, but simply not quite as expected. “They will grow, and often very productively, but you might not recognize their final mature shape as that of a carrot or potato. This is because a carrot or potato will have a harder time expanding into its mature shape in gravel than it would through soil.” However, this isn’t necessarily bad if you’re willing to branch out. As she goes on to say, “but the taste will be just as good, and perhaps you will discover some new, amusing twists to your traditional root vegetables.” Other root vegetables, such as onions, radishes and beets are slightly easier to grow in an aquaponics system.

Basil, Rosemary, Cucumbers and Tomatoes

“After about six months of operation, an aquaponics system will be more productive than a similarly sized hydroponic system,” Bernstein states. Dr. Nick Savidov of the Crop Diversification Research Centre in Brooks, Alberta, Canada, performed a two year study to demonstrate this. Using a hydroponic system and an aquaponics system, growing the same plants for two years, they found that all four plants not only grew taller in the aquaponics system, but they also had longer roots. In the hydroponic system, basil measured 30 centimeters tall after two years, while rosemary measured 31 centimeters, cucumbers measured 138 centimeters and tomato plants were 110 centimeters tall. In the aquaponics system, basil was 35 centimeters tall, rosemary was 35 centimeters tall, cucumbers were 156 centimeters and tomato plants were 114 centimeters tall.

Salad Greens and Herbs

Salad greens and herbs not only grow well in aquaponics systems, they also thrive in systems that are fairly new. As Bernstein states, “Because nutrient levels are relatively low in the beginning of your system’s life, plants requiring relatively low levels of nutrients such as salad greens and herbs will do best.” These plants are relatively easy to grow, and there is little to no need for waiting on nutrient build up.

Tomatoes and Cucumbers

Tomatoes and cucumbers both grow well in aquaponics systems. As Bernstein states, however, “save the tomatoes and cucumbers until after your system is at least a few months old and enough solids have gathered in the beds to provide the nutrients they need.” It often takes some time for pH levels, acidity and other factors to stabilize in a new system. Nutrients begin to build up as the fish waste fertilizes the plants. After just a few short months, you can grow tomatoes, cucumbers, and a host of other foods that normally require back aching labor when grown in soil.

In conclusion, just about anything can be grown in an aquaponic system with few exceptions. The pH in your aquaponics system should be between 6.8 and 7.0 for optimal nutrition, so plants that prefer a more acidic environment are not well suited for aquaponics. For example, blueberries prefer a more acidic environment that is under 7.0, and are best suited for soil. However, as Bernstein states, there are few other exceptions. “I know of aquaponics gardeners who have even grown papaya and banana trees!” she states. “Certainly salad greens, tomatoes, peppers and strawberries all thrive side-by-side in an aquaponics media bed. I’ve grown herbs of all kinds, from prolific basil plants to low-water thyme.” As she later states, “You are only limited by your imagination and your seed library.”

So, go ahead and get started on your aquaponics system and see where your imagination, and your appetite, take you. You’re certain to be pleasantly surprised.