Tuesday, April 24, 2012


I began this aquaponics project [Click Here]  with a goal to create an energy efficient system and explore the viability of a commercial system.

On March 8th I added a water heater and have maintained the temperature between 72F - 80F.  My utility bill begins and ends on the 20th of each month, so the heater was added midway through the cycle. 

The tanks are well insulated R11 and the grow room is insulated at R19.  The heater was only required several hours a day.  The weather has been slightly warmer than normal, but many days were near freezing and the glazing is not finished so I have a fair amount of infiltration.

All of these variables detract from an accurate assessment, but it is my conclusion that the cost of maintaining the heat for tropical fish and an ideal grow bed temperature is adding about 120 KWH/month or $34/month during the winter.

Recently my efforts have been to cool rather than heat.  I'm using an evaporative cooling system which consumes about 180KWH/month at a cost of about $50/month. 

My plants were lanky and pale, so on March 18 I added 270W of supplemental lighting, and they have improved.   I have also added one more light for the duck weed bringing the total to about 300W.

I have been running the lights for 18 hours a day which is consuming about 5.4KW/day.  This additional usage pushed me into the next tier and adds an extra 4 cents per Kilo-Watt, but I'll use my average cost of $0.28/KWH for these calculations.  I'd estimate the supplemental lighting adds about 160KWH/month or $45.00/month.  I will reduce this or discontinue supplemental lighting when the long Summer days arrive.

In order to reduce costs  I'll look into solar or propane heating, and I may be able to reduce the hours I supplement light or find a better glazing design.   Currently I have 40 sq ft of South facing vertical glazing in front of 25 sq ft of grow bed.   Direct sunlight is cut short by the winter season as well as the solid insulated walls and ceiling.  

In addition to lighting and temperature control the pump also consumes about 36KWH/month or about $10/month and tank lights at about 16KWH/month or $4.50

Adding this all up I get
$40.00 - Temperature Control
$45.00 - Lights
$10.00 - Pump
$ 4.50  - Tank Lights
$99.50 - Total utility per month.  

I feel the options are:
  1. Find a way to direct more light onto the grow bed
  2. Build additional grow beds outdoors for use only in the Summer
  3. Experiment with less supplemental lighting to find the minimum amount required.
  4. Change my crop seasonally and switch to cold water fish.

I am currently running the indoor grow room as well as a pond and have begun construction of an outdoor cold water aquaponic system using IBC's.  I should be able to compare the costs and production in a few months, but it seems obvious to me that the only way to make aquaponics cost effective is to raise fish that are adapted to your climate and plant seasonal crops.

Even without the additional cost of supplemental lighting my costs would still be about $50.00/month.  That is probably a break even point considering the cost of food and other items such as test kits.

I have enjoyed doing this and will continue to look at it as a $1200/year hobby with food as a benefit.

Additional advancement may come from recent technology as found in these links

Solar Grow Tube 


Saturday, April 21, 2012

Commercial Aquaponics

As I continue to learn and develop my farming skills  I keep finding these videos and articles relative to commercial aquaponics and it makes me feel that I should take this hobby to the next level.  When I watch these videos I think this is what I could be doing. So while I could simply list them in the Information page,I would prefer to create this ongoing post. Dream big!

Intensive Aquaponics with Liquid Oxygen

Heather Oaks Aquaponics

Murray Halum Aquaponics for Profit

Intro to 321 Aquaponics

Friday, April 20, 2012

Magnesium Oxide Cement

I recently learned of a fast setting cement.  Magnesium Oxide cement is water proof, fire proof, almost twice as strong as Portland cement concrete ,  more environmentally friendly than Portland cement, will not change the PH of water, sets within minutes of mixing, but it can be retarded, lends itself to free form structure, can be used with many aggregates such as sand, or wood chips, and it does not shrink or expand. 

Our Northern California Distributor just took on the Ceratech product line, and should have the product available by mid May 2012.

UPDATE 1/4/2013:
I never did make my way down to Stockton to pick up some of this product, but I did find Cement All - Rapid Set Concrete.  This is a quick experiment I did with that commonly available product which contains  Magnesium Oxide.  

To wet your appetite I'll leave this link to a site where you can see examples of what can be done with magnesium oxide cement.  Imagine the tanks, green houses or just about anything else you will be able to quickly build with this!  How about a storage shed built before lunch. This is an oven in the photo below.

Green Home Building

The method used in the photo is to soak burlap in the cement and drape it over a form.
The wall in back was created by draping over a rope.
An entire house can be erected in one day and occupied the next by spraying it on Styrofoam.  Basically creating a SIP (Structural Insulated Panels) in place.

Further info.

Article by George Swanson

Ceratech Inc

    Terry Maynard
    Ceramicrete Account Manager
    Technology Development and Commercialization
    Argonne National Laboratory
    voice: 630-252-9771
    fax: 630-252-5230
    e-mail: maynard@anl.gov).


            Grancrete is made from an environmentally friendly mix of locally available chemicals.
            “Grancrete is 50 percent sand or sandy soil, 25 percent ash and 25 percent binding material,”
            Dr. Wagh says. Binding material is composed of magnesium oxide and potassium phosphate



The Sacramento distributor will be Spec-West
Alan's Number is 916 346-8472

I'm also wondering why I did not see Airkrete (also made of MgO) sprayed on a form and made less friable by covering with MgO cement.  This would create a complete MgO structure with insulation.

Tuesday, April 17, 2012

How to Trim a Tomato Plant | Garden Guides

I planted tomato as an experiment.  I wanted to see if they would grow, and set fruit indoors, but it is becoming obvious that I will need to do some trimming as I don't have the space they require.
This article is short and simple.  It describes the method of trimming indeterminate tomato plants in order to produce a better quality crop.

Basically the method involves breaking off the suckers in order to direct the energy to the main stem.
Other sources indicate that these suckers can then be propagated and grown as individual plants which will space out the peak production over a wider time.

Some may disagree with the use of a knife or shears, opting to break the suckers off because it is less likely to cause infection and spread disease.

If the suckers continue to grow back it is important to continue breaking them off.   In addition to breaking off suckers some also recommend topping the plant near the end of the growing season in order to let the last few tomatoes mature and ripen.

How to Trim a Tomato Plant | Garden Guides

Sunday, April 15, 2012

Why And How of Aquaponics

I'm still learning about aquaponics, but I've become vested in this and want to learn everything I can to be successful.  In the beginning I ignored the problems others were having, and looked only at the positive results.  It's human nature to approach a new interest with optimism and look only at the positive results.

But I want to say right up front, this is not a hobby you can afford to make too many mistakes with.  You may watch Murray Hallam's videos and think it's as easy as plopping a few fish in a tank and growing some veggies in the water.  I don't wish to discourage anyone, but aquaponics is a carefully controlled environment that requires a lot more than meets the eye. 

A knowledge of aquaculture is a big plus.  Preferably you have experience with aquariums, and gardening before getting in too deep.  A well designed and maintained system will tend to run smoothly, but attention  to maintaining your system is important.   Water tests and careful monitoring of temperature, light, and nutrient levels is a must.

As I come across excellent studies pertaining to the design and operation of aquaponic systems I will include the links here with some commentary.  This will be an ever evolving post

To begin - Heather Oaks has made a short video of the a well engineered aquaponics system. - Heather Oaks Aquaponics.  It's very impressive and inspiring!  But remember this system is maintained on a professional level.  It does not just happen without a lot of expert knowledge, well defined procedures, and a fair amount of work.  This is dedication on a very high level, but smaller backyard systems still require the same attention.

I am not attempting to discourage anyone.   I simply wish to bring reality to the table.  Small systems tend to be more difficult to balance, but it's a good way to gain the basic knowledge of aquaponics and find out if this is for you.

This article by Keith Connolly addresses the reasons why aquaponics is superior to other methods of farming.   He also explores the requirements of sustaining a healthy and productive system with facts and scientific research.  - Optimization Of A Backyard Aquaponic Food Production System.

My blog is about my aquaponic experience.  I present it so that others can learn from my failures as well as my triumphs.  Aquaponics is something anyone can learn to do.  It's very rewarding and as the world transcends further and further from self reliance this cutting edge paradigm shift is providing a much needed alternative to our food resources.  I hope you too will find aquaponics rewarding and fun.

Saturday, April 14, 2012

Friday, April 13, 2012

Compassionate Killing of Fish

 If you raise fish for food you will need to kill them.  
There are many methods.  
Some are cruel and inhuman.  
Below you will find links that demonstrate how to kill your fish.

Aqui-S is a safe and easy solution which appeals to me.  

The following is an excerpt from:

A Report for
Philip Lymbery
Animal Welfare Consultant
February 2001

Starvation & Slaughter

Farmed fish are normally starved for about 7-10 days before slaughter. It is said that
this is to empty their gut and minimize the risk of the flesh becoming contaminated
when gutted. However, gut clearance only takes 24-72 hours. Farmed fish are
conditioned over months and years to expect frequent and plentiful feed. To suddenly
cut off that feed is likely to be detrimental to their welfare. CIWF Trust believes that
starvation periods of longer than 72 hours should be prohibited.

About 40 million salmon and 30 million trout are slaughtered annually in the UK.
That represents more animals than all the pigs, sheep, cattle and turkeys killed
altogether. Some widely used slaughter methods for farmed fish cause appalling
suffering. So much so that the perpetrators would be prosecuted if they were
slaughtering other farm animals in a similar way. Widely used slaughter methods in
the trout industry, for example, include the suffocation of fish in air or on ice. In the
latter method, the cooling effect of the ice prolongs the time it takes for the fish to
become unconscious, with fish being able to feel what is happening to them almost 15
minutes after being taken out of the water. The Government’s advisory Farm Animal
Welfare Council (1996) condemned this killing method, recommending that it be
prohibited. Nearly five years on, it remains widely used.

Another inhumane slaughter method often used for salmon and trout is the use of
carbon dioxide stunning. The bath of carbon dioxide saturated water causes the fish
to thrash around the killing container. They stop moving after 30 seconds, but do not
lose consciousness for 4-9 minutes. Salmon usually have their gills cut after stunning
and are allowed to bleed to death. The prolonged procedure is inhumane in itself.
However, as carbon dioxide causes immobility long before unconsciousness, there is
a real danger that fish remain conscious but unable to move as they are bleeding to

Inhumane and totally unacceptable slaughter methods, that can take a long time for
fish to lose consciousness and die, should be prohibited urgently. These include
suffocating fish in air or on ice, bleeding to death without pre-stunning, and the use of
carbon dioxide for stunning.

Only slaughter methods that cause an instant death or render the fish instantly
insensible to pain until dead should be permitted. These include percussive stunning
techniques whereby fish are rendered instantly unconscious when carried out
Also electrocution methods where properly designed and carried out
effectively. In the case of electrocution, the electric current must be sufficient to stun
and kill the fish otherwise considerable suffering could result.

Further information can be found at


These videos show how it can be done and demonstrate the difficulty involved.
How to Perform a Head Spike 
How to Bleed a Fish after the Head Spike
Clubbing a Large Fish
Clubbing and Bleeding
Cutting the Head Off
The Humane Way to Kill a Cray
Still Alive and Feeling Pain?

While searching for this information I found some of the most disgusting and cruel video where people were amused at the pain, and suffering of various animals.  I don't even wish to understand what these people were thinking.   Please be as humane as possible.

Wednesday, April 11, 2012

Yellow Mottling on my Spinach Plants

Update 2012/12/23
In this post I examined and searched for the cause of yellow mottling on these spinach leaves.   Finally I found that the cause was an Iron deficiency.  In the months that followed I posted several more articles with good information about this and other nutrient related signs, problems, and solutions.

For a scientific explanation of the chemistry behind the bio availability of Iron go to
[Are These Rocks Nutrient Theives?]
 [Assimilation of Nutrients]

For a detailed yet condensed collection of charts and facts go to Nutrient Deficiencies

Below is a record of my wondering search while I learned what I needed to know. I would prefer to simply delete it, but you may relateto my learning curve and find something interesting along the way.

Update 2012/06/07
I'm still having problems with yellow leaves.   I have brought my PH down from 8.2 to 6.6 and I have no salt in the system   I have also added 1/2 a bottle of Microbe Lift Chelated Iron. I'll Send an update in a few days with the results.   I have more iron on order as well as a GH/KH test kit.   Hopefully I will get this figured out.

Update 2012/04/14
"A plant injured by excessive sodium first displays mottled leaves or yellowed tissue between the veins of leaves. This is followed by leaves that are dead at their tips, at their margins, and in areas between their veins."  - WateReuse Foundation

My search for the cause continues. I had not seen any insects so I hung sticky cards to trap them.  All I got was two mosquitoes.  Several weeks ago I pushed my salt levels up to 0.35% because I had a few fish that were damaged during the transfer to the aquaponic tank.

I've been bringing the salt level down slowly and it is now at 0.20%.  In the past when I bumped salt levels up in my pond I did not notice any damage to my ornamental plants, but Spinach and Tomatoes may have a lower tolerance.

I will begin to lower the salt level over the course of the next week and see if the new sprouts show any of the same signs.

Further information:

Update 2012/04/12
After receiving assistance from Zalinda Farms Inc. , I now believe the problem may be caused by Thrip.
If not this information is still a value.  Keeping a vigilant eye on the crop is always important and Thrip is just one of condition to look for.

I have yet to actually see the Thrip, so I will purchase some Sticky Cards.  If I find Thrip I will use  Monterey Garden Spray to control the pests.  The literature indicates that it is a safe bacteria. 

Nature's Control also offers several solutions.  One is Predator Nematodes

but in an aquaponic system this may not be an option.  The instructions state "The important things are to use them within 2 hours of mixing, because after that they start to drown".  ... " They'll live longest when the soil stays moist, but not saturated with water."
I suspect they might be washed away into the water each time the grow bed ebbed and flowed.

Another solution is this Pirate Bug shown above.  They too are susceptible to environmental conditions.
"Thrips Predator Mites (Amblyseius cucumeris) are most effective under conditions of 70-85% humidity, against all species of Thrips. They will also eat an occasional Spider Mite, and other small pests. However, reports have been poor in low humidity environments, so use these predators in greenhouse and other interior locations with high humidity levels only. "

Two types of sticky Traps are also offered by Nature's ControlThey say "Customers report success using Sticky Blue Traps against Thrips & Leafminers. Especially recommended for use on roses."

I found further information at 
The definitions of INSV and TSWV are as follows:
Vectoring of plant diseases. Western flower thrips is a vector of many plant diseases, the most important of which for greenhouse producers are two plant viruses in the genus Tospovirus: impatiens necrotic spot virus (INSV) and tomato spotted wilt virus (TSWV)

Original Post
I wonder if anyone can help me diagnose this problem I'm having with my spinach.
I suspect either a lack of light, salt burn from treating my fish, or a bug, but I see no bugs.
My spinach leaves are mottled with yellow. 

The orange arrow points to a very small white area that I found behind the stem of a leaf I removed.  It looks like foam.

The underside of this leaf has very small round white spots.  This picture is through a magnify glass.

Thursday, April 5, 2012

Cycled in 4 days!

I just cycled a new 40 gallon aquarium with a 10 gallon wet/dry sump tank in four days by using water and media from my aquaponic system.

Day 1 Ammonia = 0.50 Nitrite = 2.0
Day 2 Ammonia = 0.25 Nitrite = 2.0   (added more urea)
Day 3 Ammonia = 0.00 Nitrite = 5.0  (this is the Nitrite spike)  (added more urea)
Day 4 Ammonia = 0.00 Nitrite = 0.0  (Wow,  I've never had it happen so fast)
The water was kept at 75F.

Inoculating with good strong culture from an established system will greatly speed up the time it takes to cycle a new system.  This time the aquarium was filled with water from the aquaponic system, and I used a small activated carbon filter about 4" x 6" that I had been using to disperse the water with as it poured into the aquaponic grow bed to inoculate the aquarium..

I have also notice that a wet/dry sump is especially helpful compared to a letting the water flow through all of the media.  

It's not real pretty,  but this is my bio filter.  I used a couple baskets filled with new Hydroton, you can see it is still floating.   One basket is submerged while the other is above the water level  (wet/dry sump).

My aquaponic system uses ebb and flow, but I've seen better results when I duplicate a wet/dry sump by not completely draining the grow bed.

Keeping a log

Keeping a record of your water chemistry and environment can help you understand the cause of any problems you may have later.

Here is a spreadsheet that I use to record my data.

You may choose to take samples less often, but since my system is still new I feel that every day is best for me.

Edit as you see fit.

This is an Open Office Spread Sheet.   (Please support Open Source programing and information.)

Tuesday, April 3, 2012

Activated Carbon Filters

How does a carbon filter benefits an aquarium?
Activated Carbon is amazing!  The surface area is enormous and this allows bacteria to grow much faster and more dense.  Just as we choose a porous rock for our grow beds (bio filters), activated carbon is  an ideal surface for bacteria. It's not all good because activated carbon can also grow bad bacteria that is not beneficial to our systems, but with proper care, and aeration we can avoid many of these harmful bacteria

Depending on the ionization of the carbon it also has the ability to capture a lot of impurities. For example most activated carbon filters are very good at neutralizing chlorine.

Activated carbon filters will not remove microbes, salts or nitrites, but most organic chemicals have large molecules and due to the pore size of activated carbon many of the impurities we wish to avoid are converted in the activated carbon filter.

This is how it works in an aquarium, but in an aquaponic system the goal is to utilize as much grow space as possible.   3/4" media has been proven to work best.   There are many choices of 3/4" media and I tend not  to enjoy running my hands through crushed rock. I have found smooth rock works just fine.  But recently there is a new idea being used called Bio-Char.