For most saltwater flies, I like a loop connection to the fly in order to give the fly more action in the water. In this case, I use a Kreh non-slip loop with 6 turns for tippets smaller than 1x, 5 turns for 0x or 1x, and 4 turns for larger tippet.

http://www.netknots.com/html/non_slip_loop_knot.html

If I don't require a loop connection, I use a Pitzen knot. Both the Kreh loop and the Pitzen knot test over 90 percent in tests that I have seen.

http://videofishingknots.com/pitzen-knot.html

Regards,
Ted