I use six feet of 40# Ultragreen with a small swivel to my braid. The mono is more abrasion resistant and stiffer than braids; prevents wrapping over the main line. When you are fishing deep you want to stay down as long as possible.
Good luck!
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In the legend of King Arthur, the Fisher King was a renowned angler whose errant ways caused him to be struck dumb in the presence of the sacred chalice. I am no great fisherman, and a steelhead is not the covenant of Christ, but with each of these fish I am rendered speechless.