There 's an old say:
90% of the fish are in 10% of the water, 90% of the fish are caught by 10% of the anglers.
It 's not a matter of if there are fish, you know there are fish, but where is the tricky part, fish are not evenly spread all over the water, most of the water is fishless.
Raul, you should change your avatar to Yoda with that kind of advice ;D
That water, fishless it is MMmm