Aquaculture America 2020

February 9 - 12, 2020

Honolulu, Hawaii

RECENT ADVANCES IN AQUAPONICS IN CANADA

 Richard C. Shultz* and Nick Savidov
 
 Santa Fe Community College,
 Controlled Environment Agriculture
 6401 S. Richards Ave.
 Santa Fe, NM 87508
 richard.shultz@sfcc.edu
 

 

Aquaponics is an example of integrated production system where fish, plants and microorganisms form mutualistic relationships similar to natural ecosystems. It is a significant departure from the paradigm existing in current agriculture based on monoculture. The aquaponics microbiota plays a pivotal role in forming those relationships. Among many other benefits, aquaponics allows to recirculate the same water indefinitely without necessity to discharge. Alberta became a leader in aquaponics technology in Canada with the research starting in early 2000s at Crop Diversification Centre South in Brooks and Lethbridge College. This research resulted to the first zero-waste aquaponics facility built in Brooks in 2005 due to the incorporation of the aerobic bioreactors. The bioreactors convert solid waste into soluble fertilizers, which can be recycled back to the system. Two research grants from the Natural Sciences and Engineering Research Council of Canada (NSERC) received in 2013 and 2015 allowed to further improve the technology. The conditions of the fermentation process in the aerobic bioreactor have been optimized to achieve the efficient conversion into the soluble minerals (Khiari at al 2018).  Another improvement was the development of biochar as a stable bio-filtration medium to remove finer suspended solid particles in the range 1-50 micron from fish effluent. Biochar can be produced from renewable sources, such as woodchips, straw, rice husk and coconut coir, as a result of anaerobic pyrolysis. The biochar as a growing and filtration medium in soilless culture has been developed in Alberta since early 2000s (Savidov 2013). The trickling filter can be used as a secondary water treatment after removal of larger suspended particles using more conventional methods, such as drum filters or passive settlers. The larger biochar pores can be populated by bacteria converting this material into a very efficient and affordable biofilter for conversion of fish-toxic ammonium to plant preferred nitrates. A recent study has been conducted with bamboo biochar to optimize the flow rate and the thickness of the biochar for removal of the suspended solids. Both aerobic bioreactors and biochar filters can revolutionize aquaponics and fish farming and make it more competitive with traditional technologies based on monoculture. Aquaponics has a potential to become the first food production system, which generates zero waste.