Fishing line lb test

What lb test is everybody using per species of fish? I'm 95% of the time on pan fish. I have used everything from 1 lb to 4 lb. However, I'm thinking about trying my hand at some lake trout and possibly pike. Where should I be when fishing these bigger fish.

FYI: I have landed pike on 2 lb test before lol.

I run 2-3 lb for panfish, 6 lb for walleye, 6-10 lb for lakers. I tend to always undersize my line. Not only is it more of a challenge, but I ur lakes in the Black shills are crystal clear, so I feel downsizing keeps the fish from seeing it.

For pannies and rainbow trout, I run 3-4 lb fluorocarbon line because, like Craig said, the waters here in the Black Hills are very clear. For 'eyes, lakers, and pike, I run 8 lb. Fireline Ice with a 6 lb. fluorocarbon leader. Haven't lost a fish yet to sliced line.