Sustainable Tarpon Springs - Aquaponics

No doubt most people have heard of hydroponics at this point, a method of growing edible plants in a closed system of nutrient-rich, oxygenated water without soil.  The grow medium is usually ‘sponge-like’ hydrous rocks which are immersed in the water, simply providing constant moisture around the roots.

Hydroponics is not the most natural system of raising food, but it definitely has a place in the sustainability movement because of its versatility, minimal grow-space requirements, maximum water conservation, and the minimal maintenance once the system is in place.  

You might think this system of gardening is relatively new, but the record of this system dates back to the 1600’s.  As early as 1699, it was discovered that plants thrived better in dirty water rather than distilled, before micronutrients were even on the scientific radar!

Aquaponics has ancient roots as well, but in recent times, especially in seeking clean and efficient ways to feed our growing population, aquaponics has turned into ‘rocket science agriculture’.  Aquaponics is the marriage of hydroponics and aquaculture.  

For pescetarians (fish eating vegetarians), this is a much safer form of edible fish than the ones exposed to ocean pollution, an especially heavy concern after the Fukushima earthquake with subsequent and ongoing radioactive releases into the Pacific Ocean.  (Think about the fact that pregnant women are advised not to eat fish more than once a week because of the heavy metals and other chemicals in the ocean nowadays.)

Aquaponics is sustainable and synergistic, balancing the number of fish to the biomass in the growing beds.  By-products of aquaculture are ammonia, algae, and minerals - the food that plants thrive on.  Ten times the amount of plants can be grown in the same space as a traditional garden.  There is no weeding, no fertilization, no soil pests to contend with, while twice the growth rate occurs with only 2% of the water requirements of a conventional garden!   

How does it work?  Starting with the concept of aquaculture, fish are raised in a controlled environment of recirculating water.  The best fish for this environment are tilapia, perch, trout, catfish or hybrid striped bass.  It is very important to feed the fish with a complete, high quality, floating feed and observe feeding behavior as well as regularly monitoring the water quality.

Fish waste and uneaten food accumulates on the bottom of the rearing tanks and is directed into a clarifier where through the process of anaerobic mineralization, the effluent is broken down into a nutrient-rich water for plant growth.  Iron and magnesium are the only minerals that need to be added in order to maximize plant growth.  Once broken down, this water is sent to the hydroponic plant beds.

The most amazing aspect of aquaponics is how scalable the system is - from a small garage operation to large commercial settings.  For a small operation, the investment is minimal and can be easily built with items from the hardware and pet store.  For every gallon of fish, 1/2 to 1 square foot of plant growth can be expected.  For every pound of fish, the requirement is 1-2 gallons of water.

Controlling the environment in a warmer, sunnier climate is much more efficient perhaps than a place with little sunshine and freezing temperatures, but aquaponics is being used everywhere in the world now, including places like Alaska as far north as the Arctic circle!

Of course, it is less expensive to be able to have grow operations outdoors using the sunshine rather than grow lights, but the advent of LED lights has greatly diminished electrical costs.  Passive solar grow houses are also very beneficial, and solar power in conjunction with LED grow lights is ideal.

Obviously, in a short blog I can only share the most simplified information, but there are numerous videos on the internet that demonstrate the system, as well as how to build homemade systems.  Here is one of the best videos from Purdue University:  

http://www.youtube.com/watch?v=26xpMCXP9bw 

There is a plethora of information from any of the Extension offices throughout the country, since this is being seen as one of the most leading edge, sustainable, viable, and eco-friendly solutions to tackling the issue of world hunger.  And this is already happening in garage operations right here in Tarpon Springs!