Backyard Aquaponics
A place to discuss aquaponics

I agree Journeyman I think the equation was a metaphor that got a little bent out of shape.

If you want fish as your main output you can decide how many fish you want and build your tanks and grow beds off that basis.
If you want plants as the main output you need to work out how many plants you want and then you can work out how many fish you will need to keep to provide nutrients for those plants.

When I say "work out" you will need to use the basic rules of thumb for stocking density and relationship between grow beds and fish tank size.

There is no equation that spits out the perfect answers.

I think equations can be useful... not in the examples in this thread but to give an idea as to what NOT to do. e.g. telling people 1 fish per 100L of FT is a bad equation - you can do it but there are a LOT of other factors in play, from throughput of water to acreage of GB's or filters. There are also some fairly drastic implications if/when things go wrong. 100 fish in an IBC are going to die very quickly if the pump stops.

I'm a fan of resilience, and not just in AP. Resilience is the ability to deal with unexpected events, to rebound from adverse situations. I oversupply oxygen in my system because what I have read and learned tells me it makes a more forgiving system. Low DO and the pump stops and you begin to lose fish very soon. High DO and the pump stops and you get time to come back from your overnight trip and notice the pump is off.

High stocking is fine... if you have resilience. It might be high DO or it might be a fail-over system that kicks in when the power fails.

Equations are useful to tell you what you CAN'T do rather than what you can do. You cannot stock more fish than your filters can handle - they die. You cannot grow hectares of veggies from a 100L, 5 fish system - there simply is not the required nutrients no matter how much you feed the fish.

We are still determining the parameters of AP; unlike hydroponics, we cannot simply plug nutrient bottles into a formula and determine how many lettuces we can grow because we are dealing with a living system - there are so many inputs, constants and variables it might as well be a chaotic system, and the AGW debacle tells us how well our technology goes with modelling chaotic systems.

If what you say above is true Journeyman.. then several questions arise...

Who is determining the parameters of AP... especially in a commercial sense?

What are they basing their determinations on?

And if the "system" is chaotic... how can anyone propose a commercial system... based on the inability to consistently control inputs/outputs... predict with any certainty production goals and therefore financial modelling/returns?

And for those that might be currently doing so.... if they can not determine and/or provide answers to the above criteria... are they not being unethical in claiming, or inferring that they can do so, and/or that commercial AP can be profitable... and/or what scale might be required to make it so?

Are they not basically just guessing... sucking it and seeing... dressing it up in romance with a sprinkling of snake oil?

Frankly, I totally disagree with you...

The parameters of commercial aquaculture.. are known...

The parameters of commercial plant production... are known...

Combining the two.. is just a matter of proper design and distribution... of the common element.... water and feed (nutrient)...

Hey Journeyman, I'm with Rupe on this one. Your post was interesting but you are saying that equations are useful but not one example you cite is an equation. They're all rules or guidelines.

Also I think there are at least some rules of thumb to be followed that can help someone move forward in AP which means it is not chaotic.

Sorry to disagree with you man cause you're a mensch.

Regards, Martin.

I'm totally with you on resilience though - it is an important and often overlooked element of every aspect of our lives, not just AP.

I'm totally with you on resilience though - it is an important and often overlooked element of every aspect of our lives, not just AP.

@Martinc - I haven't actually seen any equations that I would call such for AP. (:D apart from the ones people on here like top castigate with such vitriol) And every time they do, we get vagaries as to what might replace such catechisms as 1 fish per 10 litres etc.

You cannot take aquaculture and hydroponics and mix'n'match to get AP, nor does commercial plant production mean much with AP - they all rely heavily on inputs. With AP we are more dependent on nature, and nature, like it or not, IS chaotic.

Doesn't mean you can't use it, nor even that you can't make predictions, just that it IS chaotic and you have to watch for strange attractors that may eff you over as you try to make things work how you want.

If it was so easy, Rupert, to combine commercial aqua and plant, how come it is so hard to make commercial AP? You are giving schtick to bio in another thread and yet, from the evidence, he is one of the few people who has a commercial venture working. Can you spell petard?

Currently, (to answer your other hypotheticals) nobody is determining parameters for AP. You have only to look across these forums to see that chaos is the rule - how many people are struggling with AP based on identical (or very similar) equipment and practices and yet getting very different results?

Maybe Rupert you might share your 'determined parameters so we can all do a plug-in version of AP and not have to spens months/years learning the idiosyncracies of our systems.

Or should we go ask bioaqua...? I mean he HAS a commercial venture running in spite of UK floods and having to alter it a couple of times.

By building IN resilience. That's just one of the advantages one might get by trying to ensure what we live is within a world that is resilient.

If you push the boundaries in a chaotic system it WILL eff you over - the only variable is when. But build in resilience and the vagaries of chaos will not break the boundaries and you can live within the system.

As an example, let's take the guy everyone right now seems to like tearing apart. BioAqua. Here is a guy who has built a system producing quality goods that he is selling. He built in resilience by making a variety of options as outlets PLUS a variety of options within his system. The floods last year didn't kill him off nor has he opted for the various 'cop-outs' suggested as the only way to make AP commercial by a number of forum members.

We could learn a lot from him... if we are trying to be anything more than mere hobbyists who never get to self-sufficiency let alone profitability.

Or we could carp and huff and puff and keep on doing the things we do and complain about how hard it is to make money from AP. To put that in terms of this thread... we can build in resiliency and profit from a chaotic system in spite of what it might do to us or we could try to map out exact equations and watch as Nature kills our fish or plants and bitch and moan about how hard it is for AP to be profitable.

Journeyman... good thoughts... keep sharing and there are people like me newbie AP comrades who absorb everything what is best and what is workable... Thoughts on Resilience , well said.. Part of what makes Aquaponics strong is our resilience, tenacity, innovation, and our willingness to be opportunistic about our future... Let us grow together.

I am already a big fan of BioAqua because seeing is believing.

To Rupert, I get a laugh all the time whenever you tell me about "'suck and see' commercial AP system". I really do not know about your purpose and intent of repeating this 5 times in one week. But I get a feeling though... Not sure if my perspective on that is correct again.

You and some others including EB said about three variables to these ratio question. Now on to 10 other variables I could think of.. definitely there could be some others too. Guys, please add if missed out any.

1. Climatic conditions
2. Type of fish
3. Pollution in the water
4. Temperature
5. Water quality
6. Nitrogen as a variable (NH3 to NO2 to NO3)
7. Chlorine
8. pH
9. CO2
10. DO

Now critical parts - pump (flow rate), aerator, grow beds, filter (bio/mech)

Can we come at a formula/equation combining all these? Let us reveal those closely guarded secrets friends? Can we?

To say large AP is non scientific, no formulas needed, no standards, blah blah blah blah makes me want to puke.

This isn't nature, this is an "ENGINEERED" form of agriculture.

Have you ever heard of Dr Rakocy? Go read. Many formulas and standards to use as a starting point.

How many times does the same crap come back up.

I mean seriously guys, flow velocities through piping, outlet orifice sizing, tank sizing, aeration sizing, bio filtration, mechanical filtration, fish type, feed type, harvest cycles, planting schemes, greenhouse type and size, hydroponic plant growing component, I could fill up the rest of the page.

All engineered aspects of Larger scale ap done mainly through calculations.

.

WOW!! this thread is sure getting heavy ,I am almost sorry I asked the question, ALMOST.
The reason I got into AP is similar to Bioaqua and that is crap weather and I mean CRAP.

Our growing season should start in the middle of March and finish in the end of August middle of september, for the last 3 years we have had nothing but rain which has washed all the goodness out of the soil (first reason) this year our growing season did not start until the middle to end of May and even in June soil tempts were at best 12C so to me AP is the only way to go for us who live in the colder wetter climates.
I have been following a lot of the treads and what I get is that you can absolutely Engineer a closed AP growing system and except for natural sunlight and even that can be mimmiced you can or should be able to control almost all aspects of the growing cycle. I watched a Utube of an AUssie guy growing the most amazing letticues I have ever seen in an AP system and I thought I got to have me some of thoes. All going well I am going to follow in Bioaqua's footsteps next year and hence the question of Ratio's
Please give me some good guidelines and believe you me I will make a science out of it, I have lots of skills and have been in business all my life but if I thought I would have to SUCK IT and SEE I would not bother my backside just go down to the local grocery and buy every thing but the trouble with that is ONE day there may not be anything there to buy.

pat from Eire

Hi Journeyman and Ryan, I really appreciate what you both are saying here and I hear you and agree with a lot of what you say but I do think we are looking for different things from AP.

I have no desire to button down some equations in AP and I also have no desire to build a commercial aquaponics venture. What I am really looking for is a simple system where I can grow food and replace nearly all store bought veggies with home grown, the fish is a bonus. If anyone else wants to do the above mentioned things they can certainly go for it, we will be better off for it.

So when these conversations get this deep and involved I learn a lot but I don't necessarily feel the same way you do.

I don't know BioAqua and I only know Rupe a little but he has taught me a lot since I joined this forum. In fact between him and Charlie I have probably learned the most although there are numerous others which have helped me along the way including you two buggers.

Regards, Martin.

Commercial aquaponics... or any form of commercial food production.. is not "a natural system"...

It's pure bullocks to suggest so... as is the suggestion that basic formulas (as Ryan suggests) aren't known...

The problem is most hobby farms... so called "commercial" aquaponics systems.... are designed as an extension of backyard systems, or methodologies...

And most are based on a "suck it and see" approach... even if the consultants/designers/builders... don't want to admit it...

I'm not saying that the approach can't produce some good results... but I wouldn't be betting my house or bank loan on the approach as a commercial venture...

And there's no need.. the basis for correct design.. and optimal growth.. are known...

It's just the romance and bullshit of the "aquaponics is a natural eco-system"... and "closed loop" backyard scenario... that has been holding commercial aquaponics back...

For goodness sakes... the only really viable commercial AP systems around.... and you don't hear of much about those there are... are all based on the duplication of the proven UVI model...

Or, perhaps those to come... based solidly on sound aquaculture and hydroponics principles and methodologies...

The rest are based, or have grown from... pure bloody guesswork...