a lot of people rave about Izorline spectra..This line is very popular for tuna. I will put it on my tuna reels this year. Also Powerpro is a good line. Whiplash I heard is good from some people. But I would definitely stick the Izor. On the West coast thats the #1 choice for long range tuna boats.
The Trinidad can handle medium size tuna probably into 100lb..I'm considering getting one myself this year, and matching it up with a Calstar Graphiter or G Loomis Pelagic.. But I heard the reel is true amazing!!. Good luck