My commercial system plan

[adamtheha]

Hello everyone, I though I would post the tentative plan for my commercial system for some input.
I live in Southern Alberta, Canada, where winters are harsh, summer is short, but I have a HUGE parcel of land to work with, and a rural setting, so pretty much anything I want to do is good to go. No permits, fees, inspections (except the fish culture license).
Because of the climate, I have decided to culture Arctic Char, which is a fairly easy cold-tolerant species, and that will eliminate the need to heat the water, which would quickly become unsustainable in my system. They actually prefer the water around 6-12 degree C, which is quite easy to maintain, especially in the system I am building.
I have already dug a 35 x 12 foot hole in the ground, about 6 feet down, and piled the dirt on the north side of the hole. My intention is to create a below-ground greenhouse, that will take advantage of the amazing thermal-retaining abilities of moist earth, and allow me to access ground heat. I plan on running some water pipes through the ground to capture and store heat, which would then be released at night. I might do air instead of water, I haven't decided yet.
I have read of greenhouse systems in Nebraska and other cold places using this technique to keep a greenhouse above freezing, even when the outside temp is -30 C (or F). Since this is a proven technology, I'm certain it should work.
I plan to place the fish culture "zone" deeper into the ground, and use gravity to drain the water from the growbeds, back to the fish tank. This would be an ebb/flow design with solids removal at several points along the water path.

Some questions:
1. Has anyone on this forum ever tried using a below ground greenhouse for aquaponics? How well did/does it work?
2. Will Arctic Char do ok eating duckweed? I plan to make duckweed my first "crop" and try feeding it back as a supplemental feed. My eventual goal is to eliminate purchased feed, and I am willing to accept a lower growth rate as a result. What else could I feed to Arctic Char, or possibly Trout?

Problems I am aware of:
1. We are off grid, and plan to stay off. I will have to majorly beef up my RE system to support pumps and aerator devices. In the darkest part of winter, I will be scaling the system back to a very minimal level, perhaps cutting back to just some fry growing out for spring.
2. The hole I have dug is cutting into our water table, and water infiltration is a problem. I will create a spot to pump the water out, and hopefully store it above ground for my "normal" garden/berry bushes etc. The water is poor quality, but perhaps it could be added to the fish tank, if I sand filter the crap out of it?
3. Because we are so far north, we get much less winter sunlight, which means much reduced plant growth, and less uptake of fish waste. I will have to balance my fish population to counteract that concern.

My goal is to build this into a revenue stream of $15-20k per year. That could take several years, and I'm ok with that. I've got cattle, berries, and apple trees that should be producing by then, and perhaps I can quit my job and do what I truly love full time!

Any CONSTRUCTIVE criticism would be welcome. Don't tell me that the below ground greenhouse won't work, it's been done successfully already. Everything else is open for critique.

[Damon]

First and foremost, do not, under any circumstances, use duckweed in, around, or within 1000000 miles of your system. 1. once fish are trained to eat a specific food, it's darn near impossible to train them to else something else. 2. duckweed does sound attractive, it grows like a weed, and yes if you train your fish to eat it, they will, but they will also suffer. all of the information on duckweed being an applicable source of fish feed is bloated. it's like having your fish live off of tofu, instead of steak. your fish will live shorter lives, be under weight, and in all likelihood will refuse to reproduce du to lack of protein. you will only get a 25% protein to weight ration if you measure your duckweed in dry weight. and since you wont be feeding your fish dry duckweed, mainly because at that point it's just dust and the fish WILL NOT EAT IT, it's just another bloated figure. 3. adding ground water, filtered or not, into your system is risky. what ever is in your ground water, will be introduced to your fish, even the micro-toxins that don't readily filter out. you'd be better off just keeping that water separate, and mixing it with the fish emulsion water right before you water your ground plants. 4. some sun rays do make it through the clouds. i have a fiend that lives in Waimea Hawaii, and they live on the cloudy rainy part of the big island, only getting good amounts of sunlight for about 2-3 solid days a week. being in canada you are looking at seasonal setbacks, which you are already expecting, your biggest problem will be keeping the plants at 60-65 degrees F, (in you're growing lettuce) and keeping your fish at their happy baby making temp. on a side note which you did not mention, the biggest thing most people completely skip over while planning their commercial operation is the space required for seeding tables. putting your plant seeds directly into your system will result in a 70% fail rate, or at least those were my numbers under the best weather conditions (i was in hawaii, so the weather was more or less perfect.) putting your seeds into seeding trays for the first few weeks and letting them get to about half an inch tall in your choice of growing medium is more than enough time for the root system to grow to a stable point. what we say when putting the seeds straight into the system was the lettuce would make it to about 3 inches tall before they would suffer from root rot. the roots seem to need a semi-moist start, then you can plop them into the water. just like any plant, too much water too fast is just as bad as no water water at all.

[GaryD]

Hi Damon,


First and foremost, do not, under any circumstances, use duckweed in, around, or within 1000000 miles of your system.
That depends entirely on your circumstances.

In a commercial raft system, I might agree, however, in a backyard flood and drain system.....growing (for example) jade perch (which like to eat duckweed) it's a different matter entirely.

Gary

[Damon]

with growing duck weed we had problems of controlling its growth. Aquaponic systems are packed with nutrients, and when you add that to the fact that duck weed is in fact a weed and grows like on under normal circumstances... it lead to disaster on the farm i managed on more than one occasion... fish may enjoy eating it while it is fresh, but if a bad piece is allowed to survive and multiply it will continue to do so... and with multiplication you'll have the rotting sludge at the bottom of your fish tanks grow and grow and grow... until one day you walk up to your breeding tank and all of your fish are belly up because the whole tank went anaerobic because of the massive amounts of decaying duck weed. in dealing with fish tanks, no matter what kind of system you are running, you are going to have standing water for your fish to live in... and it's only a matter of time before a tiny little microscopic piece of duck weed makes it's way into you fish tank and kills the all with the quickness.... trust me... happened to 2 of our 4 trough systems, 2 of our breeding tanks, and a separate system 20 yards away, all of which went anaerobic and died. cost us about $70k, not mentioning the hours it takes to drain the entire system, bleach it, rinse it, dry it, refill it, degas the chlorine, waiting for the nutrient levels to balance, and starting over... in my opinion, speaking from experience... alot of experience... its better to stay away from duckweed, no matter what you think may or may not eat it.

[Damon]

i mean the thought of free fish food is just a down right sexy idea... but when you hear about all of the consequences of using the stuff... most people would rather be safe than sorry.

[fishfood]

Do you mean to that i better pull my system that has been running successfully on a mixture of duckweed and fish pellets for the last 4 years down and start again
as Gary said depends on your system

[Damon]

laws of statistics and Murphy's laws... if it hasn't happened yet, eventually it will. if it can happen, it will happen... to an extent you're correct in saying it depends on the system... shifting pH's and varying levels of oxygen my be preventing your system from being taken over by the duckweed, and if you want to play with fire, by all means, play away. but for the sake of efficiency, safety, and the ease of use dealing with the floating raft system, i'd keep clear of the green devil.

[GaryD]

Hi Damon,

When it comes to duckweed, I think you have to acknowledge the difference between a commercial raft system and backyard flood and drain ones.

The climate in Hawaii.....where growing conditions are as close to perfect as you're going to get...is also a factor.

Gary

[Damon]

that's for sure. the duck we that infested didn't just grow on the surface of the water, in one of the tanks that was for personal use we let it grow for a few weeks just to see how bad it could get... turns out the actually sprouted little stems and grew upwards due to sunlight competition.

ebb and flow systems would handle the duckweed better, limiting the growing conditions.

different strokes for different folks.

[RMAN]

I would not listen to anything Damon has to say. I have read through countless threads and if there is one thing that sticks out, it is Damon speaking as if his word is law. There are so many incorrect assumptions and postulations throughout his posts that it's scary. Reading through this thread just puts it over the edge. The spreading of mis-information is about the biggest problem I see in aquaponics and this name Damon just keeps on popping up. Seriously, for the good of the world...stop your madness and keep your incorrect information to yourself. Maybe they can tag you with a "buyer beware" clause.

[Pseudoreality]

I've very interested to hear on how you make out. That sounds like a good system. Too bad I leave in a permafrost area so I'd have to a go mile deep before I get any real heat. I am interested too on how hard it is to keep Arctic Char. They are by far my favorite fish to eat. I'm fortunate enough to get to travel to eastern arctic (Nunavut) often enough to keep my freezer full, but if I ever change jobs my char habbit good get very expensive.

[GaryD]

Hi RMAN,

Welcome to APHQ.

We welcome vigorous debate on technical matters relating to aquaponics but your post is personally-oriented and contains nothing in the way of technical information

For the sake of your own credibility, I encourage you to ensure that your next post is about aquaponics.

Gary

[hellbent]

My tilapias mainly eat koi food, Rainbow Koi food to be exact. Occasionally i'll feed them azolla and they will usually eat it, but not always. Seeing as how the fish taste like what you feed them, I wonder how a tilapia fed exclusively duckweed/azolla would taste like.
BTW, I have about 300 fish in 4 tanks. Generally in my tanks only the bigger ones will eat the azolla. Hope that helps.

[JohnMc]

Hellbent,

You would prefer to feed azolla over duckweed? Reason I ask is the duckweed is reasonably high in lipids where azolla is is much lower. Depending on your fish species I would think duckweed would be preferred. Opinion/suggestion?

[hellbent]

Hi, Its not a matter of preference, azolla is just what I have.
Since I dont use them primarily as feed, I havent pursued getting duckweed.
My point is that my some of my fish eat azolla but mainly eat koi food.

[Damon]

ive been out of the loop for a while now, but RMAN, the information i spread about aquaponics is information learned by doing, not just postulating ideas.

duckweed did run rampant in our breeding tanks. the decaying matter caused the whole tank to go anaerobic, and there were only 3 dozen fish in a 2000 gallon tank. it got so bad that even the 3 6in air stones couldn't produce enough dissolved oxygen for the tank.

yes, ebb and flow systems would limit the grow-ability of duck weed, but in a raft system... you could end up with the stuff in the growing troughs. if this should happen you'd find yourself having to rinse the duckweed from the lettuce before bagging your lettuce for commercial distribution. ever try to get a small piece of lettuce off of a large piece? its long a tedious work.

and gary, thanks. due to my current stand points against the FAP farm i commonly find myself at the wrong end of the insult gun. but it is what it is.

[keith_r]

hey damon, long time no see..
just wanted to ask if you saw the aquaponics setup at the galleria in cleveland, or heard about it? someone just told me about it yesterday..

[Damon]

i havent seen it yet. this is the first i've heard about it actually.

[kellenw]

duckweed did run rampant in our breeding tanks. the decaying matter caused the whole tank to go anaerobic, and there were only 3 dozen fish in a 2000 gallon tank. it got so bad that even the 3 6in air stones couldn't produce enough dissolved oxygen for the tank.


I've not seen duckweed take over in AP raft tanks before like you mention Damon, but I've seen the exact scenario play out in many earth basin ponds when they had little exposure to the wind. Typically, the end result is a serious O2 crash, followed by a massive fish kill, and a really depressed pond owner.

Again, while I haven't seen it in raft tanks with my own two eyes, I completely agree that it is possible, and that the symptoms are what you've described. I could also see it being a much bigger concern in a climate like Hawaii's, since the duckweed never really has a cold season die off period like it does in most other areas.

Makes sense to me.

[GaryD]

Hi Damon,

Glad to see you around again.


....and gary, thanks. due to my current stand points against the FAP farm i commonly find myself at the wrong end of the insult gun. but it is what it is.
Don't be too concerned, you're not the only one. For my stand on the shortcomings of the basic flood and drain system, I've been copping crap from AP's fundamentalists for years.....but science is on my side and most people are now fitting some sort of filtration to their systems.

Gary

[Damon]

most of those who blaze a trail against the grain of mainstream commonly see themselves accosted and insulted.

when it comes to flood and drain systems it would only seem common sense to have filtration. sediment would settle in between the hydroton or other growing material inhibiting the flow of water. this would elongate the drain time, if not halt it all together, making the system and flood and over flow system. lol.

and when it comes to a raft system and duck weed. i'm thinking of commercial facilities. most of which (if people were looking to actually make money and not scientific journals) would be placed in an area where the growing season, or sunny season, would be over 250 days. sun filled warm climates that would lack the cold season needed to keep duckweed in check.

im not merely postulating a theory on duckweed in a sun filled system... we spent weeks trying to skim it out of the system befor we just gave up and drained and bleached the whole thing. now place a commercial system in lets say arizona, nevada, or texas, and your looking at a lumin rating the would surpas that of the north eastern big island of hawaii.

i can see commercial aquaponic farms being placed shoulder to shoulder to solar powerd farms. both need the same climate to be productive neough for commercialazation.

yeah, you can have a productive AP systm in the norther latitudes, but you're also looking at a higher running cost, if not seasonal production.

[GaryD]

Hi Damon,


yeah, you can have a productive AP systm in the norther latitudes, but you're also looking at a higher running cost, if not seasonal production.
That's why an aquaponics system has to start out as a recirculating aquaculture system in my view.

In many parts of the world, aquaponics will not be viable because of weather extremes.....but other growing systems might be.....and, if you have set a recirculating aquaculture system, then you can cost effectively grow fish inside in those situations where plant production is not possible.

I think that the UVI/Friendly aquaponics models are climate-linked.....and largely dependent upon minimum wage employees (or funding support).....as your experience seems to have clearly shown.

Outside of the optimum growing climate, and in the full glare of competitive markets, the model just doesn't seem to stack up commercially.

The exceptions to the rule may well prove to be "lifestyle" businesses supplying a few hundred lettuce.....some packaged fresh herbs......some salad mix......smoked fish....some free range eggs......live chickens and ducks......a few quail.....some fishing worms.....rabbits.....potted plants.......or any combination of these.....to niche markets with a view to getting a modest weekly income.

Gary

[Damon]

the strange thing, and this is going to contradict my previous staement a bit, is that a micro herb set up could be productive in northern natitudes. yes the running cost is going to be higher because the whole facility would have to be indoors for year round growth, but it is possible.

since micro greens dont grow to full maturity, you could build a stackable system. im imagining something like FAP's seeding tables stacked on top of one another. instead of the walls of the seeding tables being 2x6's you could use 2x10's and add support structures in the middle of the growing areas.

since micro greens dont grow too tall the lateral lumins (light amount measured parallel to the ground) would be enough to grow on the mid-levels of the stacked unit as long as the lumins could be held around (3500) on the black box reader thingy. i know that last part sounded real scientific at the beginning and ended in the world thingy, but you know which tool im talking about. lining the undersided of the growing area with the reflective foil the pot growers line thier growing rooms with would work wonders in this area.

growth cycles in the actual system would be measured in mere weeks, and the total growth cycle from seed to harvested product wouldnt be more than two months.

of course you'd have to work out the whole water weight of the system and devise a way to make the lower levels structurally sound to hold the few tons of water weight on the teire above, but since the micro green's roots wont be all that long in the frst place, the over all water depth of each growing area wouldnt need to be but 3-4 inches deep in the first place.

ive seen systems that have a growing area on the top with the fish tank underneath. i have a friend in puna on the big island that has such a system 20 feet long by 3 feet wide with just a few inches of water in the flooded growing area part. of course he's growing exotic plants and not vegies in this system, but the principals are still the same.

a farm such as this would pack 3-4 times the growing area into each linear square foot by building upwards instead of outwards. this means your green house that is roughly 20,000 sqft could house multiples of that base square footage. heating the same amount of finite inner space while multiplying the actual growing area. supplimental lighting for the winter seasons to account for the loss of lumins, and things like wind generators or solar pannels if applicable to suppliment running cost...

its not impossable, just a bit harder to wrap your mind round.

[Damon]

funny thing is i saw an idealized structure on the 3rd zeitgeist movie. giant hydroponic structures built that were 1 acre across and 50 stories high.

the idea of building upwards ins't just an abstract thought, it's going to be put into practice if the "venus project" ever gains a foot hold.

[beelove]

check out growing power. 1 million pounds of food per in three acres of land. plus a northern local.