The perfection loop and the non-slip mono loop are two of the most common fly fishing loop knots, and on this test the perfection loop quietly outpulled the one I expected to win. A listener named Bob Johnson emailed asking how these two knots compare in 16 and 20 pound fluorocarbon for bonefish and tarpon flies. So in this How 2 Tuesday I tied both in 15 and 20 pound Daiwa J-Fluoro and pulled them on the scale to find out.
Listen now: press play in the player above and follow along.
In my test the perfection loop edged out the non-slip mono loop. At 20 pound the perfection loop broke at 19.49 pounds and the non-slip mono loop broke at 17.45 pounds. At 15 pound they were close, 10.82 for the perfection loop and 10.27 for the non-slip mono loop. I came in expecting the non-slip mono loop to win every time, so being wrong is exactly why I run these tests.
The perfection loop is a strong loop knot I have used for years in fly fishing. Knotless tapered leaders from companies like Orvis often come with a perfection loop on the butt end so you can loop-to-loop your fly line to your leader. Some anglers also use it to tie on flies. Its one downside is a perpendicular tag end that can pick up grass.
I tied both knots in 15 pound and 20 pound Daiwa J-Fluoro, slightly different from the 16 and 20 pound Bob asked about, because that is what I had on hand. I pulled each on my NextTech line tester so the comparison was apples to apples between the two knots.
The 15 pound perfection loop broke at 10.82 pounds, which was lighter than I expected, while the 20 pound version broke heavy at 19.49 pounds. The perfection loop generally breaks pretty strong, so I think the 15 pound sample may have broken a little premature. That is part of why testing multiple samples matters.
Not necessarily. These knots are close enough in strength that other factors come into play, like the perfection loop's perpendicular tag end that can collect grass, or how straight a knot hangs off the fly. I sometimes choose a slightly weaker knot for reasons like that. Strength is one input, not the only one.
Tie each knot with the exact leader you fish, then pull each on a good line scale and read the breaking point. Tie them the way you tie them every day so the result reflects your fishing. Doing it at home, before you are on the water, is how you build real confidence in your rigging.
I walk through each step in the episode. Press play in the player above.
This one came straight from a listener. Bob Johnson wrote in to the podcast email and asked how the non-slip mono loop and the perfection loop compare in heavier fluorocarbon for bonefish and tarpon flies. Those are two knots I actually fish, so the matchup made sense. I tied both in 15 and 20 pound J-Fluoro and put them on the tester. I read Bob's question and explain why it is a good one in the episode, so press play in the player above.
The perfection loop has been a strong, dependable knot for me for years. It is the loop you will often find pre-tied on the butt of a knotless tapered leader, so you can loop-to-loop your fly line to your leader. The one thing I do not love is its perpendicular tag end, which tends to grab grass out on the water. I talk through where the perfection loop fits in my fly fishing in the episode, so press play in the player above.
I walked into this fully expecting the non-slip mono loop to beat the perfection loop every single time. The scale disagreed. At 20 pound the perfection loop held to 19.49 pounds while the non-slip mono loop gave at 17.45. That is exactly why I do not trust my assumptions and pull the knots instead. I react to being wrong in the episode, so press play in the player above.
Because these two knots are so close, the decision often comes down to handling rather than raw breaking strength. The perfection loop's right-angle tag end collects grass, and that alone can push me toward the non-slip mono loop in certain situations. I will sometimes pick the slightly weaker knot for a practical reason like that. I explain how I weigh those trade-offs in the episode, so press play in the player above.
The day after this test, the lesson that stays with me is to stop assuming and start pulling. The perfection loop quietly beat the non-slip mono loop at 20 pound, and at 15 pound they were basically even.
If you fish both of these knots, tie them in your own leader and pull them yourself before you trust the result. Thanks to Bob Johnson for the question, and his follow-up on heavier shock tippet knots is coming next. Press play in the player above.
How 2 Tuesday is my weekly series where I break down one fishing skill at a time, from knots and casting to gear, tactics, and the habits that make you a better angler. Watch and listen to every How 2 Tuesday episode from Tom Rowland.
Tom Rowland · Bob Johnson · perfection loop knot · non-slip mono loop · Daiwa J-Fluoro fluorocarbon · Orvis knotless tapered leader · bonefish flies · tarpon flies · NextTech line tester · How 2 Tuesday · Saltwater Experience
I'm Tom Rowland, a professional fishing guide based in the Florida Keys, host of the Tom Rowland Podcast, and the longtime host of the Saltwater Experience television show. On the podcast's How 2 Tuesday series I break down one practical skill at a time, from knot strength and rigging to the habits that make you a better angler, in short, focused episodes you can put to use right away.
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