Fly Fishing

How This Diagram Can Increase Your Catch Rate

For those of you who enjoy fly fishing with a multi fly rig, you will know that there are a number of ways to rig up your tippet and you will have the way which is how you were taught and/or works for you. In this article I’m going to be discussing the options we have when setting up our flies and how the way in which a trout feeds may effect our hook up rate.

Before we discuss the options and their respective pros and cons, it is beneficial to discuss how trout feeding behaviour impacts these options. The diagram below tells us a lot about the way in which a trout feeds, we can use this information to our advantage and set up our nymph and dry dropper rigs in a way that gives us an advantage on the water!

Illustration of the vacuum a trout creates when feeding from

I first saw this diagram when reading an article from Midcurent about dry fly rejections. It was a very thought provoking article well worth a read though what had me particularly intrigued is the way this feeding behaviour could be effecting my subsurface offerings.

The way us above water animals eat and the way fish eat are completely different, as humans we have hands which allow us to bring whatever food we are eating straight into our gobs to be devoured. Even if we didn’t have hands it would be easier than underwater as we don’t have a highly dense medium (water) between us and our food. Why does this make it harder? Well it means that the medium (water) has to be consumed (through the gills in the case of a fish) in order to actually consume the target. If a trout didn’t use this suction/vacuum mechanism to consume their food and allow water to pass through their gills, they would be forever chasing their prey. To make sense of this just think of any time you’ve ever had the struggle of chasing a tiny piece of egg shell in your scramble egg mixture until you finally manage to jam it up against the side of the bowl.

Now bring your mind to a trout’s underwater world in a river where nymphs are regularly wizzing past while the trout draws in its prey with a perfectly timed and aimed vacuum. As the prey/nymph is freely suspended in the water without any other resistance, it would be a fair assumption that it would successfully manage to capture nearly 100% of its targeted prey.

Now imagine your flies coming towards the trout, there are now other variables. These variables result in an increase in the flies resistance to movement as it is now attached to your tippet (this resistance decreases as tippet diameter decreases), the amount of possible drag present within the line/tippet (ideally minimal to near zero) and the other fly (and it’s weight) that is also attached to the same piece of tippet. The trout then applies the same amount of suction blissfully unaware of these added variables there are two possibilities… a) the trout still successfully consumes the fly as in this particular instance the variables did not create enough resistance to over power the trout’s suction or b) The trout attempts to take your fly but does not manage to grasp it and your nymphs continue to flow down stream.

So how do we increase our chances of the above scenario resulting in Possibility A rather than Possibility B. Quite simply and I believe it largely comes down to the way in which we set up our multi-fly rig.

There are two main options that we can use when setting up our multi fly rig. There may be others but we will look at the Truck and Trailer setup and the Surgeons Knot Tag setup.

  1. The Truck and Trailer Setup
Classic Truck and Trailer Flies

The above photo shows the classic truck and trailer setup and is probably the most commonly used where I’m from. It is the option I used up until a couple of years back and certainly has it’s advantages. One thing I always noticed is when using this set up I would be catching approximately 85-90% of my fish on the point fly as oppose to the lead fly often referred to as the ‘dropper’ or ‘bomb’. I always put it down to that fly being closer to the bottom and the point fly generally being less bulky/weighted making it the more appetising of the two offerings.

However in hindsight I do strongly suspect that the reason this setup tends to do significantly better on the point fly than the lead fly is the variables I mentioned above are all working strongly against it. The lead fly has far greater resistance to movement as it has two pieces of line attached to it as well as another fly impacting its movement. This lack of movement I believe makes it not only less natural in the way it drifts but also significantly harder for a trout draw into its mouth.

I have no doubt a trout has the capability to apply the required amount of suction, but keep in mind a trout never expends more energy than it needs to and will apply the same gulp to this fly as it would any other nymph in the river.

2. Surgeons Knot Tag (or Tippet Ring)

The Surgeons Knot Multi Fly Set Up

The above diagram shows the typical Surgeons Knot or Tippet Ring setup. The dropper can be created by use of a surgeons knot tag or the use of a tippet ring. This set up is most commonly associated with Euro Nymphing but can be used to great success across all forms of nymphing, particularly indicator nymphing which is the method I actually first started using it for in replacement of the Truck and Trailer method.

When I made this switch I found I went from 85-90% of hookups on my point fly to a near 50-50 mix of catching between both flies. Not only this I noticed I was catching more fish, not just distributing the same catch rate between both flies. It definitely takes a bit of getting used to and it feels rather uneasy at first having that surgeons knot in your line as your feel it is a weak point, but once I got used to it I found the pro’s far outweighed the cons.

Once I noticed I was catching nearly equally on both flies I then went away from the mentality of having a designated “dropper” or “bomb” and having one without weight. I usually do have one thats heavier but the position of that changes depending on situations and I prefer to evenly spread the weight across both flies and ensure both flies are rather appetising offerings and weighted.

I believe the increase in catch rate largely came down to two things…

  1. This setup allows for more natural movement of both flies
  2. This setup is far better suited to the suction mechanism a trout uses to feed


It would be clear to you by now that the surgeons knot method is definitely my preferred method when it comes to any multi fly rig. I hope you may be able to gain something from the reasonings I’ve used and the discussion around the way trout feed may be something that is beneficial to your fly fishing methods in more ways than one. I would be interested to hear the set ups you use when using a multi-fly rig or if you too have noticed either method more successful than the other?

Let us know in the comments below!


  1. I Euro nymph a lot and use the method you prefer here too. But I tie a loop with a double surgeons knot on the end of slightly heavier line, going back to my indicator line and Rod, then cut the loop leaving one end that creates longer than the other. Then I tie my heavy nymph to the longer end and the shorter one becomes my dropper.
    I wonder what you think of setting up like that?

    1. Yes I have used that method before also. Is certainly a fast and efficient way to set up! Though I like to use the same tippet size all the way back to my sighter/indicator

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