Backyard Aquaponics
A place to discuss aquaponics

Although I am not completely sure, but am reasonably confident. That you can take a sample of water to local water boards to be tested. They use a mass spectrometer to check all levels.
If they can't do all levels needed then there would be commercial labs that would do it for you.

Now that could be cost prohibitive for the backyard operator, the discussion does seem to be about the different requirements from BYAP and commercial operators.

So if any large operators have the need then they could do regular testing over a period of time to establish baselines and then observation would build a level of understanding of what happens as different levels change.

From some of the reading I have done there are a few people that do have a very good understanding of some of the more in depth nutrient requirements. Some may range from being very happy to share there knowledge to treating any complex knowledge as "commercial in confidence".

Ryan from the Chatterson farms thread seem to be at the forefront of the studies.

So I believe everybody has made good point and I think the outcome is that commercial operators need to spend a lot more time & $ to check and understanding the nutrient make up of their system and the back yard people can do whatever they like as most of the time it just works.

all very good posts thanks .... here is how i see it and why i asked the first question ...

1/ i dont want to guess , guessing is dangerous .

2/ i want to know what is in my water , so that i can react in the right manner if a problem arises .

3/ AP like nature is constantly changing and is unstable at the best of times

4/ TC has shared testing methods ,anyone else testing other than master kit test ? we cant be all guessing.

5/ i find it hard to swallow the time and effort going into a system design ( small comm) and no consideration is given to the actual core of it all ...water .

Ah... the tyranny of time and distance.. and a head full of hay fever for a couple of days....
I had hoped to lead the discussion through some steps to a final position... but...

To address you specifically CDM... and your original question... from a perspective of "commercial" growing...

Not as an attack, to be pendantic/semantic... or anything else...

But so as not to assume any level of knowledge past, present or future...



You're absolutely right.... especially from a commercial perspective...


Again.. I agree completely... and from a commercial perspective.. this implies not only a need to know/measure... but also a need to respond/control...

So this implies that you need a starting baseline of your source water parameters...

A basic understanding of the baseline plant nutrient requirements through life span...

A basic understanding of what factors might alter base line water chemistry...

How your production method/design.. and environmental factors might alter your optimal parameters...

How you might control such factors...

What/how you can return to your optimal growth parameters...

And... What/how might prevent you from returning to your optimal growth parameters...



Want a bet...


Want a bet....

I rarely test my water, and in the last couple of years I may have done a test only a handful of times. But Im just a small time backyarder... and see no point.

But commercially.... you couldnt do without it.

yea im a bit late on this, but rupert doesnt attack people.
You have to give him a little leeway, sometimes his triple dots seems a little condescending depending on what was said before it, but it is not that he is trying to be condescending, sometimes his posts just lack a little information compared to what he could share.
Rupert is a good guy in general and is one of the biggest helpers here. I have much respect for him.

So what to do.. where to start... (knew I wouldn't get this in before other posts... )



In aquaponics we are attempting to essentially grow two main groups of organisms...

There are others, mainly micro-organisms that are sometimes shared by both groups.. and are beneficial.. others that might be more specific to one than the other... and some that might be detremental to one, or the other or both groups...

Straight away the latter point concerning micro-organisms and processes suggests questions about potential areas of control, or lack of control...

Both productions groups share three common requirements... water, oxygen.. and nutrients....

So, in a commercial context... the very first requirement... is a baseline water analysis...

Oxygen and nutrient requirements are known for both fish and plants.... and the chemistries of fish and plant growth known as to how they will effect water parameters.. especially in a closed loop system...

Likewise the chemistries of most of the bacterial micro-organism process are known... and chemistries can be extrapolated...

But there other micro-organism processes... many of which can be deleterious to either fish, plants or both... that need to be understood and controlled...

With media bed systems... many of the biofloral micro-organisms are probably more akin to soil based systems.. within which they perform functions that might actually be beneficial, but in a recirculating system may be detrimental, even fatal to fish (particularly).. or even plants...


Controlling such processes requires that they be both identifiable, measurable and remediable.. in order to control them...

In media based AP systems... I don't believe that we can do any of the above.. with any level of quantatative certainty....

As such.. IMO.... media beds have NO place in a commercial aquaponics scenario.. that requires levels of control for consistent production...

Quite simply aquaponics is the combination of aquaculture and hydroponic (soil less) methods of plant production....

The only common denominator of combining the two production methods.. is the water and nutrients...


Separate the two production components.... literally and figuratively....and you can then apply controls accordingly...

And you can then test/measure and control adjust your parameters...

Build your fish system with known/proven RAS principles... the first of which is to remove the factors that are detrimental to fish growth and survival.... remove ammonia and solids from the fish system water.. totally... and treat them externally...

You can then also remove, or treat any detrimental micro-organisms and/or pathogens.. make any necessary chemical adjustments... and reuse the water...

Likewise.. adopt the very same approach to the hydroponic plant production system...

The only real common denominator... is the water... and it can be used for both components.. and reused...

Nutrient needs and supply to the fish system is relatively easy... just throw in the fish feed... (yes I know there's a few other things that need supplementation/adjustment)...

It's all been worked out for nearly every possible commercial, or potentially commercial species... and aquaculture can be a highly profitable enterprise...

Nutrient needs and supply to the plant system.. is a little more complicated... but again.. it's been worked out accordingly in the same vein... and hydroponics can be a highly profitable enterprise...


The biggest impediments to commercialisation of aquaponics are... IMO...

The romantic notion that somehow aquaponics is more than the sum of it's parts... and a self-defeating adherence to a belief of a "single closed loop"...

The adherence to backyard system designs that were/are essentially based on a "suck it and see" approach...

An inherent desire, or insistence... on re-inventing the wheel...

And the apparent lack of knowledge and/or understanding of either aquaculture, or hydroponic plant production... and issues of scale.... by those promoting current "commercial" aquaponic designs...


So CDM (and others).. if you're going to pursue a commercial integrated production system...

Identify and separate your component subsystems... and design them accordingly///

The baselines for both fish and hydroponic plant growth are known and understood....

The water is the commonality... test your water (regularly).. and adjust it accordingly.... to the parameters required for optimal growth... of either system...

All you have to do then... is sell the fish and/or plants... go forth and conquer....

RoO... I'm not sure you have the right model. We are NOT attempting to grow 2 main groups of organisms. What we do in AP is attempt to take a small section of a biosphere and run it so as to be able to extract produce from 2 points in the chain.

To do that we have to input at the beginning, and because of the bacteria involved, we get to do this (mostly) once, and the chain runs, link by link until we can extract value from 2 points in the chain, hopefully WITHOUT disrupting the chain.

Mostly we have one input - fish food. If we design right, the oxygen is added as part of the system. When we fail to design right (plant level) we occasionally have to add nutrients NOT produced by the system we designed.

One system. One group of organisms. One chain. Get it right and we reap untold benefits. Get it wrong and we spend money, time and effort and watch fish and plants die. But it all comes back to, we are selecting a subset of Nature and trying to extract from 2 different realms.

As I said... in a backyard "suck it & see" scenario.... it all works just fine.... most of the time...

Ah.. yeah.... we're attempting to artificially recreate both an aquatic and terrestrial (like) environment... then trying to link the two... while attempting to artificially manipulate both.. and generally well beyond anything that would be sustainable in Nature....

So MY question still is, Rupe, do you have any recommendations for testing equipment, methods, kits etc?



No, even more important bit here is.......... Sell the fish and/or plants FOR MORE THAN IT COSTS YOU TO GROW THEM AND ENOUGH EXTRA THAT YOU CAN PAY YOURSELF!

I think this may be were way too many people go wrong when they dive into the deep end of "commercial" growing.
"you don't make any money growing veggies or fish" "you only make money if you sell them for more than it costs you to grow them."

I have seen many farms come and go (Hydro, dirt, whatever) because the farmers are not good business people or sales people or vice versa they may be great sales people but are NOT able to grow a quality crop consistently to meet the demand they have drummed up with their sales pitch.

excellent reply Rupe ... as TC asked what are your testing methods ? i am going to test all three water supply sources i have so i can determine a baseline start point ....

CDM, I am not growing commercially, although I once did grow hydroponically....

In my backyard systems I usually apply knowledge and observation... reaching for a test kit, DO meter etc... more to confirm my observations....

I'm not advocating the above approach in a commercial scenario...

Regular testing in a commercial scenario would involve the same complete analysis as your baseline source water.... using a Inductively coupled plasma mass spectrometer....

You can spot test for specific elements with various off the shelf kits... but the danger is that responding to a specific deficiency... or more correctly.. over-responding... can lead to causing another, by interrelated locking mechanisms...

On the hydroponic plant side... the standard hydroponic tests... pH, temperature and EC... would be the common daily tests.... on the fish side pH, temperature and DO, perhaps alkalinity...

There are commercial monitoring and dosing systems available... which can keep things close to baselines... but knowledge and observation are still an important tool in the growers tool bag.... as is daily data collection, which will highlight trend lines... spot testing will confirm any specific trend, but only knowledge will correct them

Bit like watching a tennis game; normally I find this boring, however the ever changing opinion/game over the years is interesting to watch.

Hay Rupert,
I'm curious as I've never quite managed to get a handle on your opinion for small farm/commercial Aquaponics. I know you don't support the idea of simply scaling up "backyard" systems for many of the above reasons you already mentioned.

You say you are not advocating the above approach. So do you think commercial aquaponics is possible? And can you elaborate on your answer a little bit. (And I can accept it if you simply say since you are not doing it and haven't seen anyone else be successful at it long term yet, you don't want to form an opinion.)

Heck I'm going through and figuring out things that do and DON'T work. But I don't think my farm will ever be on the order of "commercial grower" I'm a small farm and My plan is that it will eventually make a nice living for our family but I don't really think I ever want it to go big enough to be of interest to outside investors. Also, as with small farms, the income also comes from other aspects of the farm like the other livestock or other types of produce grown in other ways and not just on one single field or system. Having diversity helps insulate from the farm going under due to one failure, diseases or weather event as well as keeping money moving through during all seasons rather than just at a single harvest season.