Aquaponics brings together a diverse group of people with varied backgrounds and expertise. My expertise lies in only one aspect of AP at this point. I still view AP as a black box with things to be discovered and learned. I feel comfortable offering my opinion regarding water quality because it's based on 20+ years of experience in the management and operation of biological systems. I won't comment on topics where I lack experience unless it's prefaced with that acknowledgement. 

I  respect your commercial AP experience and especially your track record for starting and running a successful business. Your decision to reduce water quality testing was based on a history of daily water quality tests and the establishment of a stable operation. From a business perspective the choices you made are sound.

In regards to testing for pathogenic bacteria, the University of Hawaii at Manoa published a paper on food safety as it relates to AP.

Gina Cavaliero said:

I have been wanting to get back to this discussion in response to Terri's thoughts about all the parameters she would test for.  I cannot disagree that extensive testing would surely give a value of data that would indicate when a problem may  occur.  However, that level of testing, monitoring and then daily data input translates into labor and cost.  The level of testing and recording you are suggesting seems that it would involve at least an hour or more of daily monitoring and really not feasible considering the other things that have to occur with running a commercial operation.  If I was concerned of some catastrophic event drastically altering my system balance, I would agree that level of testing would be warranted, but I am not.  The longer these systems run and the larger (size is a big factor) they are, the more stable they tend to be.  In over four years, Friendly hasn't had any catastrophic or signficant water quality events.  They too in the beginning tested constantly as did we, but then a level of confidence is obtained because of a balance that eventually maintains.   We must consider what parameters to test for that will insure good performance while considering the cost to do it while also recognizing the value of our very intimate, daily interaction with the system. 

 

I am curious though, unless purely to test to show that there is no presence of e.coli, why you would recommend that test Terri?  These systems, if impervious to outside factors, cannot and should not harbor the e.colo or salmonella pathogens.  You agree with that Kobus?  Now I must go harvest.

Terri,  your expertise is certainly welcomed here!  Thanks for the food safety doc as well.  Being food safety is prevalent on everyone's minds lately and with good reason, I think this discussion is relevant.  I was asking why the need for pathogenic testing because I was wondering if you or Kobus thought closed loop systems with no external factors could harbor those pathogens.  I think it is safe to say that the presence of these pathogens would have to be from foriegn introduction. 

With Kobus' example of the tons of filets that could potentially be returned because of the presence of e.coli, I must conclude that the pathogen source would likely be a resullt of the most typical introductory point of most pathogens,  at processing.  Would you not?  We, or at least I am not considering that this theoretical source of contamination was the system water or fish but likely a contaminant by a worker.  Even the document suggests that the presence would be from an outside element.  I agree that data collected from various aquaponic systems would be great for the industry in general in culminating a great data base supporting that these systems can grow food in the safest way possible provided the operation employs best management practices.  Once it goes to processing, its a whole other game and set of rules.  Unfortunately it will invariably be a handling  issue that taints the industry and as Kobus said, that he smells regulation coming, so do I.  It is only my hope that the industry via strong consumer and policy education can make said regulation logical and applicable to aquaponic growing rather than the traditional soil grown regulations governing as they are now. 

While I think that we are getting slightly side tracked and heading off towards the certification debate again (drat ).  I think that there is a major distinction to be made between the two "camps" or "schools of thought" in operation in the discussion.  I'm not labelling people, I am categorizing background and mind formatting.  Correct me if I am wrong as this is an observation and in no ways an attempt to takes swipes at people. Before I became a scientist I did not view information as I do now thus I feel comfortable with what I am saying.   

Anyone with scientific, financial or engineering training are sticklers for piles of data.  We cannot deny it and often, I think the scientific method forces a little bit of overkill mentality on us.  The sky is blue because we have to disprove any of the other options, not because it is plain to see.  That said, if someone sues you one day because the sky is red according to them and you do not have the data to prove it is still blue, you could find yourself up a creek.  Thus, while someone with less of an ingrained drive for piles of data (statistical analysis of figures or working with micrometer range tolerances does this to a person) are perfectly capable of being the best aquaponic farmer ever to walk the face of the earth, I see a vital need for lots of information in terms of the following scenarios:

1.  You are questioned about your methods when there is a problem with a range of products supplied to a vendor / eatery where a quality issue pops up.  The likely outcome is the person with the least robust record keeping history will have the most fingers pointed at them, not because it is their fault, but because their defense is weakened.  Look at the shambles caused in the latest e-coli outbreak in Europe.

2.  You supply food to an entity that want to know everything about your processes for their grading / quality control.

3. You have been running your operation for some time and see a difference in yield or quality, and want to assess the underlying issue / causal factor

4. You have been running your set-up for a while and want to evaluate the most cost-effective food, plant or cultivar.  I have tripped myself up a number of times during research.  You make up your mind as you go along, but the spreadsheets prove you wrong and when you take the time to analyse the cause, you see where you went wrong.

A lot of this boils down to personal choice, thus I am not putting this forward as the "right" or the "better" option, just trying to explain how my mind works and where I see a need for dedicated monitoring.