Fly Line

Picking line for fly fishing is a complicated affair. There are many more variables that you have to account for when you are deciding what to put on your reel. Due to these variables, it needs to be reemphasized that a reel that can switch spools is an important consideration when purchasing a reel.


You have to first choose a backing. Typically, the backing is braided line that does not stretch like monofilament does. Originally the backing was made of linen but now there are many options out there that work as well or better and do not decay over time. Typically this backing is 20 or 30 pound test line and is about 50 yards long. The purpose of the backing is twofold:

1. It provides cushion and filler for the reel. By building a core of backing material you are helping the line lay smoothly on the reel and keeping the reel from getting damaged by the stretchy line essentially crushing the core of the reel. You get the added bonus of having the turn of your reel take up as much line as possible.

2. It gives you a strong backup in case you hook a large fish. The typical line for a fly reel setup for trout is only 90 feet or so. If you catch a fighter, you’ve got an extra 150 feet of back at your disposal to tire out the fish out.

Choosing Fly Line – Weight

Once you have decided which type of trout you are going for, you can pick a weight of line. Weights for fly fishing are much closer to the actual weight of the fish than for that of typical monofilament that you would put on a spinner reel. Catching a 6lb fish on 2lb monofilament with a spinner reel is relatively easy. Catching a 4lb trout on 3lb line fly line is quite a bit more challenging.

The weights available for fly fishing are 0-15. 0-4 are good for small fish, including smaller trout like Brookies. From 5-7 is the optimal mid-ground for trout fishing, with the exception of Lake and Steelhead trout which typically need a weight of 8 or above. If you read the picking a reel section, a reel that can handle 5-7lb line was recommended and 6lb line is probably the best choice you can make for most trout applications.

The things to consider when picking fly line weight aside from what you are fishing for is the conditions which you are going to be fishing. Switching up a couple weights can give you some big casting benefits. You will get better distance and the wind will influence your cast much less. However, if you are fishing the shallows the fish are more likely to see the line.

Choosing Fly Line – Taper

To add to the complexity of picking fly line, we have to pick a taper. The taper refers to whether the end or ends taper, or get narrower at the end. The function of a taper is to help your casting ability. There are four types of taper:

1. Level Taper (L)
Level taper means that there is no taper to the line. Having the same width all the way through helps them float well but makes them more difficult to cast.

2. Double Tapering (DT)
The line is tapered at both ends. This makes attaching to your backing easier as well as typing on leaders. The change in weight makes casting easier as well. This is one of the more popular types of tapering for trout fishing.

3. Weight Forward (WF)
Weight forward, as the name implies, has more weight at the end of the line that the lieder attaches to. This helps casting and allows for larger flies. This is the best choice for those just starting out with fly fishing as they offer the easiest casting.

4. Shooting Taper (TP)
Similar to weight forward taper, Shooting taper is designed for more long range casting. The first 20 feet of line is heavily weighted to allow for long distance casts. Typically, trout fisherman do not use this type of line.

Choosing Fly Line – Line Function

The next decision is determine how you need your line to act in the water. The decision to which you will use is based on which kind of fly you intend to use. Be sure to read the section on flies below before running out and buying fly line though. Again, being able to switch lines is an important ability if you find that you need a different type of fly. There are three different line functions available:

1. Floating Lines (F)
This label is straight forward; the line floats on the water. If you are using dry flies, you do not want your fly to “drown” by the weight of the line pulling it underwater. These lines are easier to see and cast and therefore are great for beginners.

2. Sinking Lines (S)
As with floating lines, the labeling is straight forward; this type of line sinks in the water. If you are using a fly that needs to sink into the water, you want the line to help with this process.

3. Floating/sinking lines (F/S) aka wet tip or sink tip lines
If you are fishing shallow areas or areas with moving water and need to use a wet fly, this is the best type of line to use. The idea is to get the fly just below the surface of the water. This is a very useful type of line to have available as a fly fisherman after river trout. This type of line has about ten to fifteen feet of sinking line at the end of the line and the rest floats. When purchasing this type of line, you will have to choose a sink rate. They are rated on a scale of 1-5, with 1 being the slowest sink rate. The serious trout fisherman would have a spool of each of these to try to best place the wet fly where the trout are, beginning with the 1 sink rate and working from there to try to find the sweet spot. If you are not that serious, you can make up for some of the sink rate by varying the fly weight or casting a bit farther upstream to give the fly a bit more time to sink. If you intend on having one F/S spool, a 2 sink rate is the best compromise.

Choosing Fly Line – Color

By far the easiest part of picking your line, the color is there for you. With fly fishing you typically have 9 or more feet of leader material and all the colors available are colors that fish really cannot see. You just need to pick a line that you can see well. Be aware that some colors get washed out in certain natural light conditions. Taking the spool of line to the front windows where the natural light is at the store may seem odd but is a good practice to make sure that the color you chose shows up as brightly in natural light as it does in the florescent store lights.

Fly Leaders and Tippets

The typical fly leader is 7 to 9 feet long including the tippet. The line is tapered which helps make the line more pliable so you can flip the fly over to present it properly to the fish. The tapering also helps make the line less visible to a sharp eyed trout.

The thick end of the leader is tied or attached to the fly line and the thin end, or the tippet, is tied onto the fly. You can either buy leader material and tippet material separately and tie them together or you can purchase them pre tapered. The advantage to the pre tapered line is there is one less knot, aka less chance for human error. Knowing how to repair a broken leader with a replacement tippet is an important skill though that should be learned.

The taper of the tippet is indicated on the package of either tippet material or the pre tapered line. The range is 0 to 8x taper. You want to match your tippet material to the hook size you are using for your fly. The way to do make sure you are using the right tippet is through the rule of three: Take your hook size and divide by 3 to get the proper tippet size. For example, if your fly has a size 12 hook, you would need a 4x tippet. If you were using a 14 hook, you would end up with 4.67. Since tippets only come in whole sizes a 4x or 5x would be appropriate. For trout fishing 3x-5x are the most common sizes used and 4x is the best overall compromise for trout fishing based on the size hooks you normally will be using.

Many of the pre tapered leaders come with quick connectors. In my experience I do not recommend them. They may be quick and convenient but can scare the fish away in still delicate spots from their splash and they are not nearly as reliable as a well tied knot. (See the helpful links in Appendix I for some great sites for knot tying)

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