I think nail knots aren't a good Idea for clear lines. I would suggest either an albright or using two nail knots to make a loop in the fly line. The later is what I do. To do this take one end of the fly line and bend back 3/4 of an inch. Then holding the line together take a 6-8 lbs piece of mono/floruo and tie a nail knot over the two pieces of fly line. Then tie another one. Try to get the two knots as close as possible. Now you have a clear loop connector. I usually cover the tag end and the nail knots with some softtex. This helps it go through the guides better. I love this set up.