Choosing a line and leader setup is not always simple if you’re just getting started with euro nymphing. While I recommend considering a specialized nymphing line if you’re just getting started, a full mono rig provides many benefits and is a good choice for a number of anglers when using tight-line techniques.

In this post I’ll describe the mono rig I use in most conditions and how to construct it. Overall I strive to keep things simple and this mono rig’s construction is straightforward and easy to maintain, not to mention fairly cost effective.

Keep in mind there are a ton of mono rig formulas out there today and you’ll need to choose what works best for you (trial and error). Just google “mono rig euro nymphing” or something similar and you should find a number of other examples on the internet. Also, books such as George Daniel’s Dynamic Nymphing are a good source for leader and rig construction.

The Mono Rig

The diagram below illustrates the mono rig described in this post. Before diving into the construction, note that while the line below the tippet ring in this diagram may be replaced frequently, the sighter, mono and backing generally are not.

Also note that with most fly fishing reels, you will encounter line pull-through when fishing this full mono rig due to the thinness of the mono line slipping through the reel frame. Luckily, there’s a fairly easy solution.

A simple mono rig for euro nymphing

Mono Rig Construction Materials

A few minor tools / items are needed for constructing this mono rig. While the UV Knot Sense is optional, I recommend it since it will smooth out knots in the rig and provide some added sense of security.

  • Fly line backing of your choice. Here the backing serves the same purpose it does with your traditional floating fly line.
  • Monofilament line that will run from the backing down to the sighter. Here we use 15 lb Maxima Chameleon.
  • A glove for your non-reeling hand. This glove is used to add tension to the line when spooling it. Without a glove your finger will get hot and potentially burn.
  • (Optional) UV Knot Sense or similar and UV light for curing.
  • Nippers or small scissors for cutting line.

Mono rig for euro nymphing construction tools

Note that the choice of monofilament (brand, thickness, color, etc.) used in the mono rig does matter. For more details on monofilament selection, see the article on euro nymphing lines and mono rigs.

Constructing the Mono Rig

This section covers the actual construction of the mono rig for euro nymphing.

For this construction “line to line” knots are used to attach the monofilament line and backing together. I prefer to keep it simple and use the Surgeon’s Join Knot (aka Double Surgeons) for my line to line connections, but use whatever you feel comfortable with. Keep in mind that the knot between the mono and the backing will only be “in the guides” when a fish pulls you down to backing.

When tying the knots, make sure they are tight before clipping the tag line back to the knot. Sometimes this requires using gloves or tools to tightly pull the ends of the line in the knot to ensure its tight.

  1. Connect the backing to your fly reel using your favorite technique. Some people use an Arbor Knot. For full details you can also see this video.
  2. Tightly and evenly spool on about 100′ of backing onto the fly reel. For this step I like to use a glove on my non-reeling hand that adds tension to the backing as I spool it.
  3. Use a line to line knot to connect the backing spooled to your fly reel, the spool of 15lb monofilament. Make sure the knot is tight and cut the tag end close.
  4. (Optional) Treat the mono side of the knot with UV Knot Sense.
  5. Tightly and evenly spool on about 100′ – 150′ of the 15lb mono onto the fly reel. For this step I like to use a glove on my non-reeling hand that adds tension to the mono as I spool it.
  6. Follow the steps in the Building a Euro Nymphing Sighter article to create and attach a sighter to the end of the mono you just spooled onto the fly reel.

A glove helps maintain tension while spooling line for the euro nymphing mono rig

Maintaining the Mono Rig

Inevitably your mono rig will get damaged if you spend enough hours on the river. For example a fish may wrap your rig around a rock causing some loss of integrity to the mono line above the euro nymphing sighter. This section has a few maintenance tips based on my experience with mono rigs.

If your mono line becomes damaged, it’s easy enough to just cut your mono line back (remove the bad end portion) and reattach the sighter. For that reason it’s convenient to spool at least 100′ of mono onto the reel; allowing you to cut sections back if they become old or damaged.

While I have found the 15lb Maxima Chameleon to withstand a lot of abuse, in general I cut my mono rigs back each year (or more frequently, depending how often I euro nymph) and reattach a new sighter. This helps ensure the line is fresh and has had minimal UV exposure to the sun.

To “refresh” my mono line I just spool off about 20′ – 30′ of mono from my reel, cut it off and throw the segment away. Then just attach a new sighter the end of the mono and the rig is ready for the year.

If you “refresh” your mono line enough times you will start to get close to the backing. At this point you basically need to rebuild the mono section by cutting it off from the backing and tying/spooling another 100′ or more of mono.


While a full mono rig maybe slightly more complicated than specialized euro nymphing line, building a full mono rig for euro nymphing is cost effective and easy to maintain. Simply spool on 100′ or more of choice monofilament line from the backing of your fly reel down to a euro nymphing sighter with a tippet ring and then run your tippet + files off the ring. If the mono becomes damaged, it can be cut back and a new euro nymphing sighter attached.