You don't need a master, all you need is go to Canadian Tire buy a box of worm and then go to Dows Lake. There is a lot of small fish and they eat like crazy.
Even a 8 years old girl can catch more then 30 small fish in an hour there.
And not all fish you catch in Ottawa can eat.
In case you ate these polluted fish, they might not kill you right away until the amount of posion from the fish accumulated enough in your body to kill you.
I mean the first time you eat the fish, you don't feel sick, but you could be food posioning next time after you eat these fish.
Good Luck