I took a trip to the Dept of Agriculture and Fisheries in Laguna (Los Banos ?).
They were really pleasant and helpful, with one of their professors taking me on a tour of their experimental fish farm facility.
At that time I was more into aquaculture.
In the end I decided against fish farming in the Phils, due to likely security issues.
Shame really because the business possibilities were encouraging.
I've just met so many expats who've lost out financially on these (bigger) ventures over the years, that I'm afraid I am rather cynical these days.