Just get some mono line. It ties easier and does not require special knots like some "superlines". As far as weight don't go too heavy as the line will be like steel cable and harder to manipulate. 12lb is about the heaviest I'd use. I stick to 8lb. An possible alternative is dental floss. I carry a wee roll in my PSK and that stuff is really tough. Also takes up no space and is already rolled. I just take the plastic case off and throw it away. Is also multi-purpose (lashing, fishing, sewing, flossing teeth) and best of all . . .cheap! Just my .02