A Very Brief History
Apparently, nobody is entirely sure where or by whom aquaponics was originated. Some people like to believe it was the Aztecs who came up with the idea by growing vegetables such as maize and squash on islands, some stationary and some movable in small bodies of water where fish were also raised. These systems were called Chinampas. Other folks prefer to credit South China, Indonesia, and Thailand for an early version of aquaponics due to the fact they grew rice in paddies along with various types of carp and eel. This would have begun around the 6th century. I couldn’t find a name for that other than rice paddy. There didn’t seem to be much development beyond that until 1969 when the University of Alchemy was established and then in 1971 when Dr. Mark McMurtry started research on the subject at North Carolina State. It was widely used in Canada throughout the 1990’s and Barbados encouraged home owners to practice aquaponics on a smaller scale so they could sell fresh vegetables to tourists on the roadside and to help the island to reduce it’s dependency on imported food. Flash forward to the turn of the century where it has recently become popular for many reasons, such as being scalable. It can be used for a large farm or for a small family to help reduce grocery bills, teach children alternate ways to feed themselves and others. When used in conjunction with vertical grow systems, it is also a space saver, allowing for the absolute best use of all area available. If one likes to eat fish, it can also be a much easier way to do so, considering just about any kind of fish can be raised in this type of system. It’s much faster too, and more of a sure thing for most of us, than having to go out with a rod and reel to catch dinner for the whole family.
What Fish Should I Raise?
Well, just about any fresh water fish will do well in an aquaponic system. Plants don’t really like to be fed salt water, and given the fact that water from the fish tank is what you would be using to irrigate and feed them, fresh water fish are the best fish to use. Salmon is just too hard to farm and Trout is good for colder climates, but they do require a temperature of 55 degrees or less. It’s perfect for Canada, but down here in Florida, it could be pretty expensive to maintain those temps., especially in the summer. You wouldn’t want to raise a fish that is more work than it’s worth. You would just be setting yourself up for failure. It seems the most popular fish to raise is Tilapia. People eat Tilapia all the time. It’s one of the most sold fish in grocery stores because of price and it has a pretty neutral taste. The water temperature can hang around 70 to 80 degrees and apparently they handle mistakes by well meaning aquaponics growers with ease. I raised Channel Catfish, and they too have a lot of endurance. There are Blue Tilapia and Silver Tilapia. The Silver seem to be the most common and don’t seem to have any regulations on them here in Florida. The Blue, however, are a much more aggressive fish when loosed on the local Bass population and you have to get permission from the state to own them. What they’re looking for, in a nutshell, is assurances from future owners that should they become disenchanted with the operation of their system, they won’t dump any of the fish into local waterways. This could cause catastrophic losses of Bass in the state, and Bass is big business in Florida. Now if you don’t care about eating your fish, or you want a small system, you can use Goldfish or any normal household aquarium. Finding a hatchery in my area seemed difficult, and I wasn’t sure how to transport 15 baby Channel Catfish anyway, so I bought them from AquaponicSource.com They deal with local folks here in Florida, and the fish arrived via UPS in very good shape. Apart from choosing the right food and maintaining the correct temp., filtration is huge in aquaponics. The waste from fish causes a build-up of ammonia in the fish tank. You move the water from the fish tank by pump or gravity into the grow beds of your plants. Ammonia is considered a Nitrite and plants don’t really care for this. That is why it’s always better to get your fish first and well suited to their new home, before you plant you vegetables. Once you’ve set up your entire system, it is best to run it for 2 or 3 weeks before you add plants. As the water runs through the system, from fish tank to grow bed to sump tank and back to fish tank, bacteria will begin to grow in the grow beds which will turn the Nitrites in to Nitrates and that is what the plants want to eat. The ph of the water should be tested on a regular basis. Plants like it low and fish like it high, so generally it’s alright to compromise and keep it right around 7. You need to test the water for the ammonia content as well, because too much ammonia left in the fish tank will kill them. In theory, when you move the water from the fish tank to the grow beds, it feeds the plants and filters the water so it can be recycled back to the fish, but what I’ve found is fish waste doesn’t really contain all the nutrients vegetables need, and grow beds seldom filter the water good enough to give right back to the fish. Extra filtering is needed for the water along it’s path and additional nutrients are needed to help your plants grow big and strong. You should also keep a small air pump running 24/7 in order to aerate the fish. They need oxygen. A light colored tank is wise, too. If you have a very large tank raising a fair amount of fish, it should be one that allows you to always see the fish. As a rule of thumb, they say you have to have 5 to 10 gallons of water for every fish. I think five gallons per Tilapia is fine, but if you raise something that gets up to around 15″ to 20″, you need at least 10 gallons of water per fish. Trust me!
There are all types of grow beds out there. Meticulous perfectionists like to build boxes about 12 inches deep out of pretty, expensive materials like mahogany, line them with pond liner material and set the drain in it at specific measurements so that every box in the garden lines up like a marching band. Others worry less about asthetics and go out to buy used plastic 55 gallon drums or IBC totes (food grade only) as cheaply as they can get them and put together just as good a system. There is a young man by the name of Travis Hughey, from South Carolina I believe, who travels all over the world helping people to set up a system called Barrelponics. That is a small set up to the right.
Up in Wyoming, a fella by the name of Dr. Nate Story developed a system of vertical farming called Zip Grow towers and he used that in conjunction with aquaponics and has since built a pretty large farm primarily around that concept. He and his crew do a lot of community work, as well as create a multitude of free videos that can be found on Youtube.com compiling tons of knowledge having to do with everything aquaponics. His site can be found here at Bright Agrotech. Below left is a pic of a small Zip Grow tower set up.
In the Barrelponic system or any system that doesn’t utilize a tower type grow style, media is required to grow your plants in. This can be clay pellets, small rock, or even vermiculite or perlite. The gist of the system is to pump water into the grow bed every 30 minutes to an hour til the bed is filled and then stop, allowing it to slowly drain. The plants get the water and nutrients it needs as well as time without water in order to take in the carbon dioxide or air as necessary. Usually, water flows into the grow bed constantly. When it reaches a certain level, as determined by the system builder, it will begin to drain. If it uses a bell siphon, the water draining out will create a vacuum and will continue to drain until all or most of it has drained from the bed, causing the vacuum to be broken. This allows the bed to be filled again and the process will continue indefinitely. In Barrelponics, however, Mr. Hughey designed it to drain in much the same way a toilet tank fills. When the water level gets to a certain level, a weight swings down to trip a lever that opens a valve. When the bed is drained, the valve closes once again allowing the bed to be filled. In either case, the vegetables get the correct amount of air and water needed to grow. The media in each bed allows for space for the bacteria that transforms Nitrites to Nitrates. Another helpful element in some grow beds is red worms, which will live comfortably in the beds and help to keep it clean.
Aquaponics can be a multimillion dollar business or a hobby for an individual or family. It can be used to make sure that chefs all over the world can get whatever they need for whatever they want to cook whenever and whereever they want to cook it. It can be used to feed the poor, employ the homeless, and allow people to eat locally more often, helping to cut down on pollution from shipping food from foreign countries out of season.
Be sure and leave any comments or questions below. I’ll get to each and every one as best as I can. Thanks for your attention.