A Look at Sinking Lines

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A Look at Sinking Lines

If there is one type of fly-fishing gear the average angler can add to their kit that opens a whole new dimension of angling opportunities it would be sinking lines. These can be used in a wide range of scenarios to take flies to fish where regular floating lines just can’t get the job done. Understanding when and how to put sinking lines into use can be a game changer for many fly fishers and these lines are absolutely necessary for some situations.

BY Gerald Darkes // Images by Rasmus Ovesen

We are going to take a look at the various types of sinking lines available today and how they can be used. Single-hand rods will be the main objective due to the extensive range of waters and species that can be targeted with them. No matter where you fish, having some sort of a sinking line with you makes sense. There are times that this can make or break a day on the water.

OK, so why do we need anything beyond a floating line? I can just use a weighted fly and maybe some split shot to take a fly below the surface, right? True,

that will work in situations where the fly is dead-drifted under an indicator or fished Euro-nymph style. This setup certainly has its place and catches plenty of fish. But you can only do so much with weight and a floating line.

If you need to swim the fly below the surface for a distance and have it hold depth for a period of time, the sinking line comes into play. Sure, you could use a 20-foot leader and heavy fly and maybe get a fly down around 20 feet (if you could even cast it), but as soon as you begin the retrieve the fly it is going to start to climb toward the surface.

The faster you strip, the faster the fly climbs and the higher it goes. The fly doesn’t spend any amount of time at depth. Realistically, a floating line with a weighted fly that can be cast is limited to depths of 3-5 feet or so.

The sinking line will hold the fly at a certain depth for an extended period. To understand this more, let’s take a look at the various types of sinking lines available, how they are made, and their application. Fly line technology has advanced significantly and modern sinking lines are precision fishing tools. They allow us to cover the water column from just under the surface to depths down to around 30 feet (10 meters).

Sinking lines allow us to cover depths of down to around 30 feet.

A Brief History

The earliest sinking lines were used in big-water applications. Sections of lead-core trolling line with a monofilament shooting line like Amnesia behind them and set up as shooting heads. These certainly took the fly down, but were somewhat hazardous to cast as the lead-core was not very flexible. Tangles as well as having to duck on the forward cast to avoid injury was common.

Use of these lines was limited. They were used mainly in northeast striper fishing and targeting Chinook range of uses- freshwater and saltwater, tropical to coldwater, and to fish from just under the surface to depth. Because of the toxicity issues of lead, tungsten powder use began in 1980. The amount of tungsten powder added to the PVC or urethane base of the line is carefully controlled to achieve certain densities which control the sink rate of the lines. Lines can also be made of multiple densities.

If we look at sinking lines that are currently offered by manufacturers, we find a staggering assortment of options. Trying to select the best options for your needs can be intimidating. Let’s take a look at the various sinking line designs available and where they are best applied.

Sink Tips

In this application we are looking at one-piece lines where most of the line floats and a portion of the line sinks. These are not tips added to a two-hand line to swing flies for steelhead or salmon. These lines are made to fish flies from just below the surface film

salmon in deep coastal estuaries. They were really not practical as a general fly-fishing line at that point due to the weight that needed to be cast. Most were used on 10-weight outfits.

Eventually tungsten powder was mixed into PVC and flexible shooting heads were made. Varying the amount of powder and PVC helped control the grain weight and sink rate of the head. Full-sink lines were then created where the running line and belly were integrated as a single unit. This were then manufactured into various line weights. Scientific Anglers introduced these first lines called Wet Cel in 1960.

As mentioned earlier, line technology has advanced to a point where sinking lines are made covering a wide to depths of possibly 10 feet. They are weight-forward designs where the length and density of the sinking portion varies.

Sink-tip lines are offered in specific line weights and normally in three primary sink rates. Intermediate tips sink at a bit over 1 ips (inches per second) - 2,5cm/second. Sink 3 average 3 ips (7,6cm/second), while Sink 6 is 6 ips (15,2cm/second). These are usually found down to 5-wt. Lighter line weights are not really practical and the use of the tungsten powder needed to sink the line will exceed the designated line weight.

These lines are primarily used to cast and strip streamers in lakes, rivers, and streams and work chironomids, leeches, and various nymphs in stillwater situations. They can be used wading and from a boat. The base material used in line construction is clear and has a density slightly more than water so the intermediate tips can be kept undyed for a super-stealthy presentation near the surface.

Varying the length and density of the sinking section controls how deep the fly can be fished and how fast it can be retrieved. For example, short, clear tips (5’ / 152cm) are used to fish small flies with a slow retrieve near or in the surface film.

A longer (15’ / 457cm) Type 6 tip will keep a streamer down 6 feet or so on a fast retrieve. With the main body of the line floating, the shorter the tip and faster the retrieve, the shallower the flies will run. As most of the line floats, they are easy to pick up and recast.

As fly fishing horizons have expanded, so has the application of these versatile lines. They are now built up to 12-wt. for use in extreme environments such as the Amazon and saltwater flats world-wide for peacock bass, tarpon, permit, giant trevally, and other gamefish.

Integrated Shooting Heads

These lines take the shooting head concept to the next level. The shooting/running line and head are integrated into a single line. No more loops to worry about when the line goes in and out of the guides. The running line is a length of level fly line, then there is a short taper to transition into a single-density head or belly of the line.

These lines are made to cover water quickly and efficiently. They load quickly and shoot easily for distance. Some are made to fish high in the water column, while others can reach significant depths. They are designed primarily for streamer fishing with powerful turnover of flies on the cast and holding depth on a rapid, active retrieve.

The heads on these lines vary from 25’ (7,62m) to 30’ (9,14m). The running line can float- best for wading, or sink slowly for use out of a boat. They are built with different grain weight heads that cover several line weights. The weights of these run from 150 grains. to over 500 grains. and the heads can range in density from floating to fast-sinking. The most recent versions density changes in the head.

These are probably the most versatile of sinking lines as they have such a wide range of use. Line cores and coating can be varied to maximize performance in various water temperature ranges from cold-water trout to saltwater tropics. Combined with various density and sink-rates, we can select a line tailored to a specific application.

The great thing about these lines is the ease that they can be cast for distance with minimal effort. Once the head is out of the rod tip, there is no need to continue false casting. In fact, the cast will just fall apart if you just gradually work out line. You go from the weight of the head to a virtually weightless running line. There is nothing to hold the weight of the line once it is out of the rod tip.

Instead, once the head is out of the rod tip a bit it is easy to just shoot the line on the forward cast and let the weight of the head carry the running line out. Incorporating a double haul will add additional distance. Most beginners work way too hard when casting these lines at first rather than letting the rod and head do the work. A short period of time is usually all that is needed for most anglers to adjust these lines.

With a known sink rate, it is easy to count these lines down to a specific depth (within reason) where you want to present the fly. The maximum practical depth for these lines is around 30 feet. With the long head and thin running line, the fly will stay in this range for an extended period of time on the retrieve. Simple math shows a Sink 6 head (6 ips rate) takes 20 seconds for the line to reach a depth of 10 feet. This actually gives pretty precise depth placement of the fly- especially on stillwaters or areas of slow current.

If there is current or boat movement involved, this depth will decrease a little. But after a bit of experience with these lines you will get a good feel of where the fly is at all the time. After catching few fish, the confidence factor kicks in and using these lines becomes an easy task.

We also see these lines used in true big-game situations. Built on extra-strong cores of up to 100 lb. breaking strength and heads up to 750 grains, these lines are made to tackle a variety of bluewater species such as sailfish, tuna, giant trevally, and marlin. They load heavy rods quickly and turn over the largest flies.

Full-Sink Lines The last line type we are going to look at are full-sink lines. These have actually been around a long time as earlier lines such as those made from silk would sink when they got wet. These lines had to be dried and then dressed in order to fish on the surface as they were generally used. There is very little in the literature mentioning early lines used to present flies below the surface.

We noted earlier that the first modern sinking lines known as Wet Cel were introduced in 1960. Here the entire length of the line was made to sink below the surface. These were revolutionary in the sense they could be cast as a regular fly line and were made in specific line weights. This opened up a whole new range of fishing opportunities for fly anglers.

Full-sink lines mean precisely that- the entire length of the line is made to sink below the surface. These can range from super-slow-sink designs made to keep flies in the surface film, to those designed to sink to depth rapidly and crawl flies along the bottom. Line densities are made to cover all levels of the water column.

These lines are most used for stillwater applications, that is lakes and ponds with little current present, although they are often fished from a drifting or slowly moving boat. They have reached their present level of sophistication for use on the reservoirs of the UK and lakes of western North America. Here trout are the main target and anglers need a series of lines to cover the needs for a season of fishing.

Many of these lines are quite specialized. For example, “hover” lines stay in the film, suspending just below the surface and keep flies in this zone. They may be used with floating flies to minimize the drag created when a floating line is pushed by wind. This helps keep the fly floating naturally.

There are also lines where the full length can be clear to reduce visibility and give a super-stealthy presentation. These clear intermediate lines can be a game changer on clear, calm, flat water, turning reluctant fish into active feeders. These lines also have applications for other types of fishing such as stalking carp on shallow flats. Saltwater designs are also appearing for similar use.

The early full-sink lines were a single density and a fast-sink version would tend to sag from the rod tip creating slack and reducing the ability to detect strikes and get a good hook set. This problem was addressed by the introduction of multiple-density lines. These lines are densest (sink fastest) at the tip with less density at the mid-section and back end. The goal is to achieve a straight-line connection from the rod tip to the fly with minimal sag. This improves bite detection and allows for a better hook set when a fish hits.

These lines have two or three density changes in them and the premium versions have a graduated change between densities to eliminate hinging when being cast. They are offered in slow-sinking to fast-sinking versions with the angler selecting the line best suited to the depth range being fished. As with the integrated shooting heads, a countdown method can be used to keep the fly in the desired fishing zone. Once again, we will put the practical depth range to around 30 feet (9 meters).

There are also situations where the fly needs to be crawled just off the bottom. Here, the fastest sinking section may be in the middle with a lighter density at the tip. This keeps the fly off the bottom, visible and away from weeds and debris. If fished more mid-depth this type of line gives the impression of a critter swimming towards the bottom, often a great strike trigger.

These lines can become quite sophisticated. “Hang markers” are added to the line at a specific length from the tip. This tells the angler how much line is still out to help gauge fly depth and when it can be easily pick up and cast again. After a bit of experience, these lines become a key tool for having consistent success on the water.

Add Ons

There are various leaders and tips that can be added to conventional lines to take flies a bit below the surface. Poly leaders are short, polymer-coated monofilament leaders available in different densities. Though designed for swungfly use, they can also be added to single-hand lines to get the fly a bit deeper on retrieve. The fastest sink version is normally used here. These do not significantly increase the line weight for casting as long as they are used with a 7-wt or heavier line.

Some of the tips that are made for Spey line use can also be added to single-hand lines. Here we need to be aware of the grain weight of the tip being used so we do not overload the rod when casting overhead. For example, the manufacturers standard for an 8-wt. line is 210 gr. If we add a 10 ft. Scientific Anglers TC Tip that weighs 120 gr, we are 330 gr. total. More in the range of a 11-wt. line for overhead casting. Probably too much for our 8-wt. to handle

Adding tips is best done with heavier weight rods, 8-wt. and above, to give some added versatility if needed. You can quickly adjust a line by the addition of a tip if you don’t have a suitable sinking-tip line. This is something to be aware of and while the norm with two-hand lines, it is outside the box with single-hand lines.

In the opposite of this concept, a short floating tip can also be added to a sinking line to work a fly just off the bottom or keep it above weeds. In any of these applications, casting may be compromised a bit as these tips will likely hinge when cast overhead. However, this is not a permanent set up, rather it is a quick solution to a problem that needs to be addressed at that time. Whenever you are on the water, it pays to be flexible and adjust to the situation you are faced with.

Wrap Up

No matter where you fish, sinking lines will likely increase your fly-fishing opportunities and success. Fly line technology continues to advance. Durable coatings with wider temperature ranges extend line life and effectiveness. Controlled stretch cores give better bite detection at depth and allow easier hook sets. Stronger cores allow larger fish to be targeted. As the limits of fly fishing continue to expand, sinking lines will play a major role.