Indoor is tricky, you need to make sure that your antenna is pointed directly at the CN tower and is as high off the ground as possible with as little between the antenna and the outside world as possible.  People getting 15 HD channels are using outdoor antennas and are placing them high up.  If your in an apartment then you need a south facing window, for the antenna, a south facing balcony is better.  The 4 bay antenna that is about 1 1/4m long with built in reflector is your best bet.   Use only R6 cable to run from the antenna to the TV, you want to avoid any kind of splitter or connector along the cable.