The economics of aquaponics

[chrisc]

Hi All...

Straight out I would say im interested in the whole idea of aquaponics. The idea of taking use of the waste of one thing to feed another is great! However, in reality would i be wasting my time doing a back yard job as far as monetory loss (or prehaps gain??) goes...

Without having a system myself i feel a little in the dark with this, but im percieving that I would end up paying a moderate amount of cash for the initial startup (not a huge issue if it pays for itself short or long term), but im concerned that ongoing operations would proove painful... ive looked on ebay for fish food at it seems to be a very expensive item for the sort of fish that are spoken about on this site (i guess the exception would be Talapia, i believe it can, or does eat algee?).

Or have people found a different way to feed their fish?
Or simply found a cheaper food?

Has anyone put together any stat results, or at least have their own personal conclusions on the day-to-day running of an aquaponics system?

Would love to hear from you all...

Regards,

Chris

[Whodat]

I don't have any useful information or experience to share, but I see that you've not had a response in the week since you've posted. So I will tell you my plans for the future. I hope to grow as much as I can, such as in the worm beds that I have where horse manure is growing redworms, and hopefully have something like a biopod or a homemade version to produce black soldier fly larvae. Also leaves and grains being grown both in my AP grow beds and the main garden's raised beds. Between the rabbits, chickens and fish, I hope to use the waste products of each to help produce the food for the others. If I can't produce enough good quality feed, maybe it will augment the commercial feed enough to keep it economical. I hope to hear from others you have more experience and can tell of their operations and how they offset expenses.

[svc]

There is an in depth analysis here... http://www.pdftop.com/view/aHR0cDovL2JhY2t5YXJkYXF1YXBvbmljcy5jb20vVHJhdmlzL0Nvc3RCZW5lZml0QW5hbHlzaXNvZkFxdWFwb 25pY1N5c3RlbXMucGRm
The conclusion seem's to be capital can be payed off on a turn key system in 2 - 2.5 years, I believe if you are cost conscious and make your own it would be even less. It can become quite an addiction and it is very easy to go overboard on spending though.
Jade perch doesn't seem to get a mention, I believe you can supplement their food with greens from the garden, just chuck in a whole lettuce etc. and they will eat it.

[Damon]

having managed a commercial sized Aquaponics system i can maybe help this one out.

The price of fish food is well... pricey... but you have to look at this as an input/output kind of system. yes you are feeding the fish (input) but its the usage of its waste in an undetermined or unquantified out put. at least for now, there really is no definite ratio concerning the amount of food fed per amount of waste created, and due to the differences of metabolic rates in different fish species, or even different fish of the same species will undoubtably vary.

One trail i was on while on the farm was seeing how far we could stretch the fertile water.

we used a floating raft system, and according to everyone before us you needed X amount of fish to adequately raise produce across X amount of square feet of grow bed... well, we ran a commercial sized experiment... kind of foolish, but it ended up working... what we ended up doing was keeping the initial amount of fish, but tripled the amount of growing area, and we found no relative change. and since we didn't have to add more fish mass, we kept consuming the same amount of fish food, but our production amount tripled, thus lowering the actual running cost, mainly because your running cost is never a solid number, it's a percentage...

what i'm thinking was happening is the fish waste isn't just powering the plant growth. when you make a floating raft system, you're, for all intensive purposes, making an ecosystem. it's not just a fish = plants equation... there's algae, microbes, bacteria, smaller fish, detravours, and many other things living in your system. the more you have living in your system, the more of a food chain starts begins to form, to where a lot of what is eating in your system, isn't exactly eating fish food... the food chain of bacteria, gammarus eating decaying biomass, and many other small things happen in the system that happen in normal ponds and streams, due to the cleanliness of the water, and it all helps the food production aspect.

we expanded the grow area without adding more fish, and all we did was make a bigger place for the microbes and other things to live, and if they live, the produce waste, and if they produce waste, they also help fertilize the water along with the fish poo.

I know this isn't exactly the magic answer to how to operate cheeper... but take it as going the other way. look at it as how to produce more with your current cost constraints.

[chrisc]

Thanks for all the replies so far, really appreciate your thoughts and the information. I particularly enjoyed the document as well with its comparison figures - since i live in the same state as the author! hehe

Keep well everyone :)

[emcgee]

Be careful when you look at the numbers of this report. The author is assuming that you will be able to sell all of your fish and vegetables at retail, which would certainly have the shortest recovery of investment and be the ideal. In most cases, I don't believe that this is the reality. The successful commercial operations that I know about sell almost all of their output at wholesale, which is a LOT less than retail.

Of course, if you are looking at it from the perspective of using everything yourself and not having to buy it, the numbers may be accurate. But I think this would only be true with the smaller systems, as I don't know too many families that can consume the entire output of the larger systems.

[Damon]

though we sold our lettuce in bulk, we sold to costco, which only posted an 18% up-charge when they sold the lettuce to the public. selling your produce at the retail price would be the best way to go, but it's also very unlikely.

and really, the only system i can imagine actually eating everything that i grew would be one that maxes out at 2 troughs of grow area that are 4ft wide by 30 ft long, and even then, a strict vegetarian would had trouble eating all of that produce unless they grew a great diversity of vegetables, and even then, there's only so many things that will grow well in thee systems... so unless you really really really like lettuce... you can count out the complete consumption of a family sized system...

[GaryD]

Hi,

The whole matter of economic sustainability around backyard aquaponics (for most people) is open to question.

The capability of most kit systems (inasmuch as there has been any attempt to quantify productive capacity) has been overstated. No-one that I'm aware of has been willing to clarify the assumptions that underpin their productivity claims.

The job of sorting the aquaponics wheat from the chaff got a bit of a boost recently with the release of Dr Wilson Lennard's Backyard System Design Tool. The calculator and the explanatory notes will certainly rein in some of the more extravagant claims. Even more importantly, it will enable prospective purchasers of such kits to calculate their capabilities.

emceegee.......I don't think that it's unreasonable for people who make backyard kits to link their ROI to retail prices since that's what most people would be paying if they were not growing their own food.

I think the issue with such kits is that the production capabilities are either over-stated or not stated. Either way, making purchasing decisions becomes difficult.

Gary

[emcgee]

emceegee.......I don't think that it's unreasonable for people who make backyard kits to link their ROI to retail prices since that's what most people would be paying if they were not growing their own food.

Gary

I absolutely agree (and I think that's what I said, although maybe not very clearly). If it's just for the family, the figures may be accurate IF they can consume it all. If it is for sales, or there is a lot of waste, I think they are a bit optimistic.

[GaryD]

Hi emcgee,


If it's just for the family, the figures may be accurate IF they can consume it all. If it is for sales, or there is a lot of waste, I think they are a bit optimistic.
Sorry......I failed to make the connection with your point. I agree absolutely.

Accurate information about the productive capacity of aquaponics systems (rather than unqualified guesstimates) is essential if the prospective purchaser is to make informed buying decisions....and if the sellers of such systems are to have any credibility.

Gary

[GaryD]

Hi,

I went back and had a much closer look at the ROI report.

The report is premised on theoretical assumptions rather than practical observations.

While you can take a good guess at what a system might achieve (based on realistic assumptions), you need to factor in operating offsets.....which the report author appears not to have done.

For example, the author has used feed conversion ratios to determine the amount that a given number of fish would consume and its cost. The feed conversion ratios might be applicable in a commercial situation where everything is being managed closely, but it's unlikely that those ratios would be achievable in the ad hoc feeding arrangements that would apply to the average backyard environment.

The number that caused me most concern was the "one kilogram of fish and seven kilograms of vegetables (of unspecified types) for 22 litres of water." This is grossly inaccurate - in terms of the amount of water that would be consumed by the plants.

The bigger issue is that the amount of vegetables produced in the system (and their subsequent value) seems to be premised on this ratio.

Another questionable assumption is that of the fish production.

The report appears to assume two neat six month growing seasons of optimum fish growing weather. Of course, our experience tells us that Barramundi will feed like demons at 24 degrees C but will eat nothing as you drop below 18 degrees C. Similarly, trout will eat hard at 16 degrees C and pass up the food at 22 degrees C.

In any given year, insects may impact vegetable production (and in a recirculating aquaponics system there's a limited amount that you can do about it) but there doesn't seem to be any allowance for pest damage.

Of course, as Emcgee pointed out, not everything that is grown will be eaten. A lettuce that is eaten is arguably worth a couple of dollars but, if it goes in the chook bin, it's value drops to five cents. Similarly, a nice ripe tomato may (at the peak of the season) be worth 50 cents.....but, if it has a worm hole in it, it's good for the BioPod and is worth nothing.

There are sufficient inaccuracies and incorrect assumptions in the report to bring its whole worth into question.

A supervised growing trial would enable a much more realistic assessment of what is possible.....and what the ROI would be.

Gary

[Crusty]

The report appears to assume two neat six month growing seasons of optimum fish growing weather. Of course, our experience tells us that Barramundi will feed like demons at 24 degrees C but will eat nothing as you drop below 18 degrees C. Similarly, trout will eat hard at 16 degrees C and pass up the food at 22 degrees C.

Entertainer System: "This system is capable of producing up to 50 kilograms of fish per year." from the advertising on the site.

The report states as fact not based on experience: For the entertainer system, average 45 barra or trout.

Wilson Lenard states in his report for the same system the following:
http://www.backyardaquaponics.com/Travis/Backyard%20Aquaponics%20-%20media%20bed%20model.pdf

Summary from Wilsons model based on 45% protein which is very low for both barra and trout and 1% feed rate as noted in the document as a standard feed rate for fish over 100 grams. I have not been able to find any reference to any species in Australia that is fed at that rate below 500 grams.

Just the same Wilson says the following about the Entertainer as far as fish production capacity goes:
Between 17 and 20kg per 1000 liters (this system has a 1000 liter tank that we are not sure holds 1000 liters at operational height).

What that looks like really?:


The web site advertises 50kg of an unknown species of fish.
The report says 45 fish
Wilson says max 20kg of fish (assuming the 1000 liter tank supplied with the kit holds 1000liters)... regardless or worm function lol.

It seems the kit sellers have embraced Wilsons model vehemently, which I have watched them joyously celebrate with interest. I look forward to when they apply it to their advertising. How do you grow 50kg of fish in a system that is capable of 20kg? I wonder what happens if you feed the fish 1.5% to 2% body weight per day and/or the protein is above 45%...

"Live barra $12/fish" (which is $24/kg). The reality is it is $15/kg or $7.50/fish which has been steady for many years. You and I can buy them at this rate. Boned and filleted barra in the supermarket run at $17/kg (remember there is no guts and what not). There are some boutique prices at the high end of the retail restaurant market that will receive salt purged barra at $24/kg, but definitely not a backyard raised unit.

At $640/m2 of grow space it makes me wonder about Mr Chiangs motivations for the false implication these systems are cost effective for the families and the communities on larger scales. I would go so far to encourage larger groups to seek legal action should they not perform as advertised.

We can not look at one and not the other.

The PAP site advertises the following: "This kit will grow out 50 Murray Cod or Silver or Jade Perch or Barramundi."
http://www.aquaponics.net.au/product/prod98.htm
I was hoping this would have changed since the release of Wilsons model....
Wilsons model says the following: 10kg to 12kg per 1000 liters. The tank on this kit holds 800 liters which means this set up is good for 8kg to 9.6kg of fish (about 16 to 20 fish).

http://www.aquaponics.net.au/PAPreport.pdf

If I put the following fish in this kit without taking into account climate or skill level.
Murray cod - 50 = 600grams in a 1.2 years for plate size = 30kg/1000liters
Silver perch - 50 = 450grams in 1.5 years for plate size = 22.5kg/1000liters
Jade Perch - 50 = 500grams in 1 year for plate size = 25kg/1000liters
Sea Perch - 50 = 450grams in 1 year for plate size = 22.5kg/1000liters

All of the above are more than 2 to 3 times the recommended 8 to 10kg of fish. But that will depend on what you call plate size. If you grew 50 of any of the advertised fish at the recommended density they would weigh at harvest about 200grams. Don't know about you but I would not eat a 200gram fish, especially the ones listed above.

[maximus]

I red with interest Dr Lennard analysis, however I noticed that the calculation of the system uses the UVI commercial raft system and not the gravel GB.
consequently the mentioned 60 g m2 of fish input is based on nitrification on the raft surface+roots area+ nitrification tank (Net tank for UVI) and uptake of minerals from the plant. Therefore the studies are math calculation or actual experiment?

Then I have a question of my own. Would not be economically more sound to shift from a classic flood and drain system to an Hybrid system where water from FT is pumped to a GB (gravel) and by gravity to a lighter and cheaper PP food grade container (using raft technique) then by gravity to the FT.
This would increase the nitrogen uptake from plants allowing higher fish stock (if opportune aeration is provided)

Cheers

[GaryD]

Hi Maximus,


I red with interest Dr Lennard analysis, however I noticed that the calculation of the system uses the UVI commercial raft system and not the gravel GB.
consequently the mentioned 60 g m2 of fish input is based on nitrification on the raft surface+roots area+ nitrification tank (Net tank for UVI) and uptake of minerals from the plant. Therefore the studies are math calculation or actual experiment?

The Backyard System Design Tool was developed for use with basic flood and drain systems.


Then I have a question of my own. Would not be economically more sound to shift from a classic flood and drain system to an Hybrid system where water from FT is pumped to a GB (gravel) and by gravity to a lighter and cheaper PP food grade container (using raft technique) then by gravity to the FT.
This would increase the nitrogen uptake from plants allowing higher fish stock (if opportune aeration is provided)

Some people use a flood and drain grow bed to filter solids out of the water column prior to having it flow through raft tanks. The Backyard System Design Tool also makes allowance for this option, too.

I'd rather use a swirl tank or sedimentation tank and a packed media filter to capture and process solids than a grow bed........it's cheaper, has a smaller foot print, is more effective and easier to maintain.

Gary

[Damon]

I have those records that you speak off... pretty sure im the only person on the planet with the records of pounds harvested per harvest pounds averaged per raft, and the records of the amount of sunlight that produced those numbers.

The records i kept on the "un"friendly aquaponics farm were good enough to forecast the projected growth rates of their commercial so well that after 3 months of watching them i could free base (project in my head) the amounts of lettuce that would be produced as far ahead as the weather men could forecast the weather conditions.

I believe those are the kind of records the people wanting to go commercial are looking for. : )

[Damon]

And i appologize about the late reply, since ive left their farm ive been forced to return to ohio and pick up a job bartending at a local indoor water resort, the people of ohio know this place as the great wolf lodge.

While that seems unimportant at the moment, ill let whom ever reads this know that while shmoozing patrons into leaving behinde larger tips ive made a few contacts in the food distribution industry very interested in organic produce. For those of you that don't already know this... the organic food craze has yet to really gain a foot hold in the bread basket region of the usa, making everyone aware of that knowledge very excited at the aspect of getting in on any aspect of the organic food movement, commercial food suppliers included.

So really what im getting at is, i have the knowledge, and people that are interested in buying and inturn reselling produce, but im lacking the farm. So if any of you reading this has the piece of the puzzel that im missing, pleace feel free to contact me, because im always looking for a job back in the AP field.

Nomadatlop@msn.com is my email address and its connected to my phone so ill get an email as fast as id get a txt.

Thanks all, ill be back soon.

[GaryD]

Hi Damon,

I believe that the operating success of the Friendly commercial operation (and that of UVI) has a lot to do with their choice of tilapia as a fish species and (in both cases) a very hospitable growing climate.

I question that the same model would translate quite so well in other places where tilapia is not permitted and where the climate is more varied.

Your thoughts?

Gary

[Damon]

After seeing the lettuce grow just fine in waimea, which hasmush less sunlight compaired to honokaa the amount of lumins comming through cloud cover is actually just below prime for lettuce. They only averaged a clear sunny day 2-3 days a week.

As far as fish go, using local fish that are used to the regions climate would work. Sure you would have to keep trout water cleaner than channel cat fish water... but thats all just the cost of profuction vs. The value of output. If your main focus is produce, you would really only use the fish to work the farm and small personal sales any ways due to produce grown vs. Fish mass necessity. The only added feature for people growing food in norrthern climates would be the need for a green house, but since the fish in the area are used to the colder climate, keeping the green house and the tank water around 65 degrees F wouldnt prove to be such a problem... theres already dirt farmers in my area turning a profit that way in the winter as it is, without the growth rate benefits of AP.

Also where im at we're lucky to see direct sunlight teice a week at most in the winter, and again local farms like green house growers arent having much of a problem over the winter. In fact they just increased their facility size and staff last month, the exact same time we saw 6 inchs of snow fall over night.

[maximus]

Hi Gary,

I agree in most countries a sedimentation tank and a tank used for air stripping and ammonia conversion is the way to go for commercial operation. However having cheap land, very cheap labour and gravel (egypt) I think to integrate a small gravel GB (with worms) in order to have enought surface for nitrification and possibly using worms as biological sistem to convert sludge into nutrients (thanks to aerobic bacterial mineralisation).

Hi Damon,

I agree with Gary regarding the system used by friendly aquaponics. Their system is working because they use Tilapia on a climate that do not require to heat or cool the water.
I am assessing a commercial system in Switzerland using Perch, but it seems we will be loosing money on the fish side.
The only way to make a commercial viable is if would be possible to certify organic the veggies. We are working on that but is rather difficult because only soil based crops are allowed the organic label here.

cheers

[Damon]

Im kind of selling out on of my key playing cards when it come to trying to secure a job in A, but there is a company that certifies AP for organic. Oregon Tilth is the company that certified the friendly farm.

And like i stated before, there are already green house operations in my area already turning a profit, which means their green house is already 65 degrees plus... the ambient air would be enough to heat the tanks for perch, bass or even ornimental koi.

The biggest thing, like ive stated before, is the coice you'd have to make between using AP for raising fish of for raising prroduce. The friendly farm was grosly over stocked with fish when it came to running the farm. Low end estimates were at 7500 - 8500 pounds of fish mass with a growing area of well over 10,000 sq feet of growing area. And as we were finding out, you'd only need about half of that after the water nutrient levels were set up.

Also with growing in a green house you space is better used, being able to grow close to 70 lettuce plants in the same area that you'd only be able to grow 10 -15 if they were plannted in soil. Now when you add the growing capacity to the increased growth rate... is far more efficient to use AP.

Yes, you would use more electricity, but your ability to grow more food faster in the same space would trump the cost increase... so yes, you may be paying an electrice bill thats 80% higher than normal, but you're also increasing your yeild by almost 250% and getting that yeild almost 50% faster than conventional means...

Breeding fish indoors is just a bad idea to begin with, mainly for the electrical cost of the high heat, but if you're just using the fish to grow the produce and selling the smaller amouunt of fish locally to help offset other costs instead of being a main supply of income, the running cost of a green house AP farm is cost justifyable.

Again, it all comes down to making that initial choice of fish vs. Food in the colder climate.

[ecosystem]

Damon-
I remember reading something about Friendly AP saying that they lose money on the fish side which is only about 8% of their revenue, and the rest of their revenue was from produce. Do you know how they were determining the cost of the fish - was it just in fish food, or did they include some costs for electricity, maintenance, and fish wrangling as well? From what it sounds like, the logical thing would be to raise the smallest amount of fish possible to still get the benefits of AP, or as some have suggested, eliminate the fish completely(no offense meant to any AP people). It seems that what you are saying of fish vs. produce, you would focus on the produce with a minimum of fish in a colder climate - but why would that be any different in a warmer climate if they are still losing money on fish? If the goal is to maximize profitability(or attain profitability) there must be some optimum ratio of fish to produce. From what little I know so far, this is still a big question mark with a multitude of variables, from climate, fish type, produce mix, water quality, fish food, greenhouse or not, even greenhouse material, etc. It does sound like you are convinced that the cost of doing AP is definitely worth it based on knowledge that you have acquired at Friendly AP - that is very encouraging!

[Damon]

Earlier thismornng (east coast time) i stated in an email based on this discussion that there is really no base line, or determined minimum, of fish necessary actually quantified.

If you are making the choice to go the way of produce its better to consider the fish as a running cost rather than a a revenue generator. The sizes just dont match up. The amount of grow area needed to filter a commercial fish operation is well... lets just say crazy huge...

It'd be better to keep fish sales a private matter and sell off your over stock, rather than trying to match up the two ideaologies. One of the systems on he friendly aquaponics farm has 3 times the amount of grow area going off of one tank than was proposed by the UVI systems... thus stretching the amount of waste provided by a set amount of fish mass.

Also their systems are grosly over stocked with fish, and as u said, feeding fish that you dont need becomes an unnecessary cost. So really, to streamline production costs youd want to find that magical baseline of fish mass to limit the running cost.

[hellbent]

Is the overstocking of the fish in their system detrimental to either the fish or the plants? they seem to be making money from it and i would consider the fish, as you say, a part of the cost of doing business. selling off the fish would offset the feed price, at the very least.

here in hawaii, a 25lb bag of rainbow koi food its $25 of 3.5mm size. the bag is lasting less and less long as my fish keep multiplying.

[Damon]

The main problem with an over stocked system is you'll have an increased system demand for disolved oxygen. The more fish you have, the more oxygen you need to be putting into your system. And the more oxygen you put in, the more electricity you use, so it ends up being a double cost... extra food and extra oxygen... if its found that a certain amount of fish is only what you need and anything above can be considered wasteful if your not selling it... kind of like the saying goes, " if it isnt helping its hurting."

Other things to watch out for is the increase of ammonia and changes in ph... you'll hit a limit to where the plants wont be able to process all of the waste... thats why a commercial fish farm would need thousands upon thousands of grow space if you were to keep it a closed loop system without mechanicaly filtering the water...

[GaryD]

Hi,

I think the idea of running a lightly stocked AP system to grow plants might be OK for backyard purposes. Indeed, if you're running a basic flood and drain system that's probably the only option available to you.

When it comes to a commercial system, however, I suggest that there are probably more cost effective ways to grow vegetables than running a lightly stocked raft system - like hydroponics.

Comparisons between raft systems and soil-based plant production are interesting but ignore the fact that there are other plant production systems - like NFT. When it comes to stacking plants into a greenhouse, NFT can be every bit as space efficient as raft.....and is likely to be a lot cheaper in terms of capital outlay.

Once you change the fish species, you change the whole ball game. Most species will require water of better quality (containing higher oxygen levels) than tilapia.......and cooler weather will mean that you get fewer crops (that take longer to grow) than in a warmer climate like Hawaii or the US Virgin Islands.

Once you factor in fish species and cooler climate to the aquaponics equation, you end up with a production unit which starts to look quite different to the Friendly System.....in terms of size and complexity.......to produce the same amount of fish and vegetables.

These are just some of the reasons why commercial aquaponics has been so slow to take root outside of those places that offer ideal growing climates and/or cheap labour.

Gary