Dr Wilson Lennard on Aquaponics Today

Dr Wilson Lennard is an Australian scientist with a PhD in Applied Biology. He has studied and installed commercial aquaponics systems around the world. In this extended interview, over the coming days, Dr Lennard will discuss the state of play in Aquaponics research today, as well as his views on how to successfully run a backyard system, a commercial system, his new fish sizing calculator, the alarming flood of “aqua-shysters” as he calls them or marketers that are jumping on the Aquaponics bandwagon and what’s in store for the future of Aquaponics on the planet.

In general terms, what are your scientific qualifications?

I have a BSc (Bachelor Degree In Applied Science – RMIT Uni 1990), an Honours Degree in Applied Biology (Aquaculture manipulation of yabby reproduction – invitro fertilisation, egg raising and semen extraction from the Australian Yabby – 1992 RMIT Uni) and my PhD in Applied Biology (Commercial optimization of aquaponic systems with relation to adaptation to Australian conditions and fish species – 2006 RMIT.

How did you first get interested in Aquaponics?

I first became aware of aquaponics in the mid 80’s when my interest in aquaculture started. However, other things like Uni etc…got in the way and i didn’t go back to it until 2000 when I was working and decided I wanted to do my own aquaculture research.

It was then that i became aware of Jim Rakocy and his work and I did about 12 – 18 months research (literature work) and then wrote a $300,000 research grant proposal to RIRDC (Rural Industries Research and Development Corporation – federal government). I was unsuccessful with the grant application but RIRDC offered me a PhD scholarship, which they give 3 per year for the whole of Australia, so i think they were interested and I was very lucky!

Some people say Aquaponics is just a recirculated Aquaculture system with a Hydroponics component tacked on. Is this how you view Aquaponics?

My initial interest was from treating aquaculture waste, so yes, initially I saw aquaponics that way. However, over time, working with systems and seeing how they operate etc…I have discovered that they can be much more. However, I think it really depends on the hydroponic component and how that is designed. Some hydroponic approaches help build a more complex ecosystem than others. I would say that media bed systems have the highest ability to be an ecosystem, because media appears to assist the range and number of micro-organisms a system can support. Media also helps provide a higher number of niches for the bugs to fill. The next is deep flow and the last is NFT; I have an NFT system in NZ and it has proven more difficult than any other system and it behaves more like a traditional hydroponic system than an aquaponics system. i would now only advise NFT as an add on to an existing system which can take the additional plant growing capacity; fully NFT aquaponics requires skill and because the water volume is so low it needs to be understood that an ecosystem doesn’t develop as efficiently as the other methods. NFT as a few channels added to an existing media or deep flow system is fine, as you have the ability of the deep flow or media already built in there to produce the ecosystem.


Who in your view are the main Aquaponic players in the global arena?

Well, I work solely in the commercial realm, with a large emphasis on science, so I can only comment on that. The main player, guru etc…was Jim Rakocy, and he still is, but he has retired and will now concentrate less on aquaponics as a whole. A true pioneer with 30 years aquaponic application – you cannot beat that! Another is Dr Nick Savidov from Canada. He has done some great research on aquaponics and is developing more sophisticated approaches to the hardware utilized in systems. There is also Carlos Leon in Mexico, who assists many people to build commercial-scale, UVI style systems in Mexico. There are now emerging a few other Uni’s around the world who are beginning aquaponic research, so they will come into the picture soon as well. For example, I know of several research groups (government and private) starting in the USA and others in Israel, The Netherlands, Iran, Hawaii and South America. There are also several groups who have been around for some time and looked into aquaponics in the past and have now come out of the wood work now aquaponics has a larger public profile, which is fair enough. Rebecca Nelson and John Pade in the USA are also prominent in the USA and are expanding around the globe and have done great work spreading the word. There are others out there who say they are experts etc…but I see little from them and some of them are basically ripping people off and telling a whole lot of lies in their own commercial interests; some are quite prominent and have their supporters, so maybe they know more than I do about them, but I am not convinced and just see “money making” as the main motivation. I measure my interest by the commercial and scientific sectors, which are still very young and in development.

Is Aquaponics research still ongoing and being studied? How much is still unknown?

As I said above, aquaponics research is starting to be taken up by other Uni’s etc..and new players are coming along. Many of them are repeating work already done, which is frustrating, but I guess required for them to learn. The UVI model has been around for 20 years, but no one seems to take the outcomes from that seminal research as a starting point and they all seem to want to do it all over again. I probably get around 10 papers per year to review for journals and many of those have nothing new or novel about the research and in fact, most of it seems retrograde at best with them making the same mistakes we all made in the past!! There is still plenty to learn, as for all science, and it never will end. I think the next frontier is for all to realize that you can actually run these systems more efficiently than they currently are. My approach uses a good percentage less than the fish required by any other commercial approach, and I think it could be improved still beyond that. The other frontier will be microbiology based, which will hold many interesting things and efficiencies for systems. This includes initial ID of the species inhabiting the systems, but then moves into how can we manipulate things so we get the bugs we want in greater numbers to do all the work for us. In addition, a lot of aquaculture feed research is now based on trying to replace animal proteins and fats with plant proteins and fats. When we have a fish feed that all fish will eat and doesn’t require wild caught fish to make it, that will be a revolution for aquaculture and aquaponics. I also think that will link in with us choosing vegetable eating species over carnivores and even culturing vegie eating fish just to produce feed pellets for carnivore fish. I think the future of aquaculture is this style of multi-level approach where we simply grow some fish on vegie diets so we can then grow the fish we like to eat by feeding the vegie eating fish to the carnivores.

Continued: Dr Wilson Lennard on the Backyard Aquaponics craze and why people are getting it wrong.