Thursday, August 29, 2013

Aquaponics Is Not A Sustainable Form of Agriculture

Aquaponics has been touted as a way to save the world from the destructive and wasteful agriculture practices used on most commercial farms which is clearly not sustainable.. But just as raising cattle for meat, raising fish on farmed grain is also costly to the environment.
Much of the grain used to produce fish food is GMO;  raised using large amounts of fossil fuels for fertilizer and machinery in order to produce a profit while neglecting the environment.

Perhaps aquaponics will find a place in outer space, but while we are still here on Earth, aquaponics will remain a romantic attraction blindly portrayed as sustainable, and ecologically sound by those who fall in love with the technical wonder of soil less gardening.  For some the full experience includes the ability to automate, and record  data from sensors.

Clean, neatly segmented water processing stations each providing an optimum environment for bacteria, roots and water quality at the expense of outside energy and natural resources.  Computerized systems can even be monitored and operated remotely from a smart phone miles away.
Certainly easing the harvest of wild fish is a good thing, but we often overlook the large picture. Kinda like growing corn for ethanol. What a short sighted idea that was. Aquaponics is not easing the harvest of wild fish as well as it appears. The food we feed to the fish is made from wild caught fish. And while that source is comprised mostly of fish with little commercial value, and waste from the processing it still places a burden on the wild fish population. For more about the analysis of fish food read

Aquaponics uses less water than soil based farming, but it comes at a cost is the environment, and fossil reserves which seems to be overlooked. All along I have promoted energy efficiency in aquaponics, but the numbers still come up short as I demonstrated in another article 'Energy to Produce Vegetables' .  The caloric value of the food produced does not match the energy required to operate an aquaponic system. The pumps require more energy than is grown by a very large factor; sequestering far less carbon than it releases. Some aquapons are supplementing light, and heat during the cold season. This puts aquaponics so far into energy debt that it becomes absurd.

This government funded aquaponics research system has deep pockets and no regard for wasted energy

Bottom line - aquaponics is fun, it's interesting, but it's not saving the world as a sustainable form of agriculture.

So what can we do?  The answer lies in simply helping, and growing with nature rather than in spite of nature.

Plant in soil, according to the seasons.  Conserve water by creating collection and recollection areas,  use green mulch,  alternate and grow companion crops, build healthy soil with micro-nutrients, and microorganisms, never let the soil lay bare,  Use only safe pesticides if needed.  Never waste a good thing - compost and use compost tea and EM.   Use bio-char,  humus and rock minerals.  Gather leaves in the fall or just let them provide the natural benefits to your soil by leaving them alone.  Pay attention to micro-climates, and take advantage of shady areas near fruit trees.  Let some beneficial weeds grow in order to bring nutrients up into the top soil.  Love the worms and bees, and feed them well.  Plant flowers among your vegetables.  Do not till your soil.

Wear sun block, and a hat!
Wicking beds and Hugelkultur beds conserve water

The Basics of Natural Farming

The common theme between Hugelkulture and Wicking Beds is water supplied from below the soil.  These are both considered Permaculture.  It may very well work in our favor to integrate these methods with aquaponics.  This new hybrid system is called Earthan Beds

Thursday, August 22, 2013

Airlifts, Geysers and AquaZen

I want to begin by saying I am not an expert with airlift design.  My results  differ from others who have spent more time experimenting with airlift technology.

I like airlifts because they are less expensive to operate and can be built for only a few dollars.   Airlifts aerate the water and are able to pass objects such as way ward fish without clogging.  They have no moving parts; instead they rely on an external air pump which would in most aquaculture systems already be present.

In the video below I experimented with three types the pumps.  A simple Airlift, a Geyser Pump and an AquaZen Airlift.  This video documents the results.

This video shows me running five different airlift configurations.
All of the designs performed very close to each other.
Some factors that may be influencing the differences are the diameter of the pipes and the number of turns.
Each test was performed with a 200 lpm EcoPlus 7 air pump running at 93W.
The vertical pipe was submerged 24-1/2" and the rise was 13-1/2" +/- 1"

Test #1 Simple Airlift with Separator - 5 gal/62 seconds
Test #2 Simple Airlift w/o Separator - 5 gal/58 seconds
Test #3 Geyser with Separator - 5 gal/74 seconds
Test #4 Geyser w/o Separator - 5 gal/50 seconds
Test #5 AquaZen - 5gal/58 seconds

In each case the separator appears to actually reduce the performance. Sorry I did not run the Aquazen test without the separator.  I believe the loss of performance is due to my design and I will try to make this part more efficient.

The Geyser and Simple Airlift performed as well or better than the AquaZen. But there are many factors that may have been overlooked. As far as I know the check valve was installed correctly and there were no significant leaks. The submersion and rise were kept within a 1" tolerance and the barrel was filled to the top each time.

I hope others will take the time to build and test these, and other airlift pumps. More data might help. It may also be that they each operates best at different lifts. I still have so much to learn