My magic recipe for trout and steelhead is berkeley trilene xl mono for mainline and seaguar pro for a leader. I use a #14 barrel swivel and attach a leader of approx four feet of flouro . The trilene is inexpensive very durable and casts like dream . The seaguar gives you the stealth advantage of invisibility as well as the mono floats while the flouro sinks which is another benefit if you drift or float fish much like i do .
Another nod for GAMMA line. Strongest line I have ever used. I use 6-20 lb test depending on what I'm fishing for and what technique I may be doing. The other plus is that it's based right here in Oil City PA.