Cold Water Aquaponics - 3.5 Year Summary

For the past 3.5 years, I've been running an aquaponics setup in my basement.  Aquaponics is a combination of aquaculture (raising fish) and hydroponics (growing plants in water, without soil).  Most people who set up an aquaponics tank live in warmer areas, such as Australia, Hawaii, and California.  I live in an area of Colorado that gets much colder in the winter, which makes it much more challenging, and potentially more expensive.

I started this blog with a lot of technical detail, in case other people who live in cold climates want to set up an aquaponics system.  This post is an overview of my experience (with lots of pictures) for people who don't want to spend hours going over my wordy posts.  If you're looking for specific information, such as water temperatures, how to set up the tank, etc., take a look at my 2011 posts.

Equipment - Fish tank and Grow Beds

My setup consists of a single fish tank (150-gallon stock tank) and two grow beds (60-gallon stock tanks), which are filled with gravel.  The grow beds are on a platform above the fish tank.  A submersible water pump in the fish tank pumps water into the grow beds. Once the water gets to a certain level in the grow beds, a siphon causes the water to drain back into the fish tank.   The fish poop in the water fertilizes the plants, and the gravel in the grow beds filters the water before it is returned to the fish tank.

Fish tank on bottom, grow beds on top.  Left grow bed is empty, right grow bed is filled with gravel (grow media).

Siphon - this is in the middle of each grow bed.  When the water gets near the top, water is drawn up through the brown tubes and drains into the fish tank below.

The siphon is surrounded by a larger pipe and covered with screen. This keeps gravel from being sucked into the rubber tubes and clogging the system.

This is the drain that comes out of the bottom of the grow bed and drains the water back into the fish tank.

I added an empty flower pot with fish filter material under the drain pipe.  This catches some of the gunk that the gravel doesn't get, keeping the water a little cleaner.

I got the information on how to set up the siphon from a paper published by University of Hawaii.
http://www.ctahr.hawaii.edu/oc/freepubs/pdf/bio-10.pdf

Fish

Tilapia are used in most warm-water backyard aquaponics systems.  Tilapia are warm-water fish that grow quickly, taste good, and usually reproduce on their own.  This is great for warmer areas, in which the water won't need to be heated.  Because heating adds to the complexity of the system, as well as the cost, and an additional point of failure, I chose to go with trout.

My water temperature is usually around 45 degrees (F) in the winter, even indoors (if it were outdoors, it would be frozen for most of the winter).  Trout do fine in the cold water, but they grow more slowly than tilapia, and they don't breed on their own.  I have to drive several hours round trip to replenish my stock once or twice a year.  If I get them in the spring, when they're small, they only cost me about 50 cents each.  However, cold-water fish die quickly if they don't have constant water circulation, so I have to rig up an air pump on my truck when I transport them.  I use a large aquarium pump and run an extension cord from an inverter in the cab of the truck to the air pump in the back.

Per the fishery guy's recommendation, I transported the fish in a large (clean) trash can in the back of the truck.  I drilled holes in the top and ran the air tubes from the air pump into the water in the barrel.  A couple of notes if you do this -  put stones on the air hoses to weigh them down.  On one of my trips, the hoses popped out of the water and I lost 35 of my 50 fish.  Also, make sure you tie down the barrel really well - another lesson I learned the hard way (see post "A Fish Story" if you want to  read about this failure).

Air pump taped to the barrel.

View from above - fish in a barrel.

 

The first set of fish I had was so feisty, and the water so high, I had to put chicken wire over the tank.  I read about several people who had fish jump out and die in the middle of the night.

Here are some random fish pictures from the past three years.

This is about how big they are when I usually get them.  About 5-6 inches.

This is after about six months.  I think this is a 12-inch plate.

This guy got BIG.  Over 14 inches long.  The lump on his head was from my repeated attempts to "dispatch" him quickly, but that didn't work too well.  If you raise your own fish and are looking for a humane way to dispatch your fish, I recommend this video.  Don't watch it if you don't want to see a fish die.  

This is the same fish as above.  "Grandpa fish."

Grilled trout dinner.

Trout and koi sharing the tank.  The koi didn't last long.  I don't know if the trout attacked them, or if they had a disease from the pet store.

Here is some information on aquaponics fish.

Plants

Most plants don't do well in cold water. The water in my tank gets down to about 45 degrees (F) in the winter.  Most plants do better in water temperatures of 65-80 degrees (F).  I couldn't even get wild flowers to grow in my grow beds.  Just like people, plants don't particularly like 45 degree water on their roots.  Also, the window next to my tank faces east, so it doesn't get much sun.  Even with a grow light, I get yellowish plants in the winter.  Plants do OK in the summer, but they spend most of their energy trying to get to the sunlight coming through the window.

lettuce sprout

bean sprout

Bean plants

Bean plants

Bean blossoms

Beans,  My bush beans grew like pole beans, trying to get to the light in the window.  For the size of the plants, I would have gotten hundreds of beans outside.  Inside, I got about 25 beans.

I ordered a few strawberry plants.  I got about five flavorless strawberries.  It was still kind of cool, since they showed up in the middle of December.  Nice to see some color that time of year.

Accidental Oak - An acorn from a different planting project fell into my grow bed and sprouted a Mighty Oak.  It's been there for a coupe of years now.  It loses its leaves in the fall, but then greens up again in the spring.  

I added coir (coconut husk) to the top layer in an effort to get stronger plant roots.  I also have a fan blowing on the plants to simulate wind.  I do not have a fan strong enough to simulate the winds we get, though!

Here is another picture of my strawberries.  You can see how the plants spend most of their energy on growing big leaves, probably trying to survive until the water warms up and they can produce some fruit/vegetables.

Here is information on plants in aquaponics.

May 2014 Update

I've still got five trout in the tank.  I threw a bunch of wildflower seeds in one bed, just to see what happens.  The plants have grown, but no flowers, probably due to the cold water temps.  Now that it's starting to warm up, I expect the cilantro to grow a lot more quickly, and maybe I will get some flowers.  Because we don't have A/C and we heat mostly with a wood stove, the temperatures inside the house aren't as constant as they would be with central hear and air, so the water temperature fluctuates with the seasons.

Instead of typing a bunch of stuff, this time I decided to just narrate the video.  Not sure if anyone can understand my mumbling over the sound of the water draining...

UPDATE:  After I uploaded this, I watched it and realized you probably can't hear anything I say, so here's a rough transcript:

Me: "Blah blah fish blah blah....I still have five fish....one is a lot bigger than the other.  Let's feed them.  They love dried meal worms....blah blah blah....
Here are the plant beds."
Cat in the backgroud: "meow."
Me: "In the left plant bed, I planted a bunch of wildflower seeds.  They haven't produced any flowers yet, probably because the water is too cold.  Oh, that looks like some little flowers coming in.  In the right plant bed, I have some basil and cilantro.  And here is Armando, the fish keeper."