For transparency's sake I must begin by saying that I have never attended an aquaponics course nor received certification through an agency. That being said, I have delved into the many available courses and guides just to see what is offered in the aquaponics field. The majority of the educational aquaponic services were 3 hour long farm tours for between 50-100 dollars a person and weekend long seminars for home systems for a couple hundred dollars. Few outliers included online seminars or classes that spanned multiple weeks, but those tended to be close to a thousand dollars.
What I mean to emphasize with this observation is that the resources for learning how to run an aquaponic system are limited by the sparse physical locations of aquaponic farms or the high price of online courses. On top of that, the time and material required to cover the intricacies of aquaponics cannot be condensed into short lessons for a weekend.
If aquaponics is truly something that interests you use that curiosity to be proactive about gathering aquaponic knowledge. There is no better way to learn than to get involved, jump in, make mistakes and ask plenty of questions.