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Going Deep Fly Fishing

Getting down deep with fly fishing gear.
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The sun rises over the Northern Colorado plains and a glimmer of light touches the surface of the lake. The suns rays reveal a lake edged by ice with snow still covering the shaded regions around the lakes shores and beyond. Only days earlier the entire lake was covered by ice and is now open, open to the fisherman that dare wander into the frigid water. The fish still lethargic from the cold of the dark winter below the ice are now gaining in activity as each day proves to increase the temperature of the water and consequently increases the activity of the fish.

This scene is common this time of year and often proves difficult to the warm water fisherman wanting to get on the water after vowing to watch their last southern bass fisherman on OLN, at least until next winter. The fish are certainly less active than during the peak of spring or the beginning of summer. However, they still need to eat and the question of where the fish are usually means probing the depths and usually encroaches on an area of fly fishing that many have not fully understood or find difficult and often filled with much effort and few fish.

To explore this we first need to understand that even slight increases in temperature can greatly increase a fish’s metabolism and consequently their activity levels. Ice off means the temperature is increasing. For many species more tolerant of the cold like walleye, perch and pike it means spawning is near and often hails some of the most productive fishing times for the species of the whole year. However, for other species like bass, bluegill, and wiper the fish are more acclimated to warmer water and are still deep. The water in the depths is more stable and often many fish will remain deep until the water warms sufficiently.

The first step to solving this puzzle is the equipment to use. For most situations on lakes in the Rocky Mountain west, 6-7 weights rods are the best choice unless going after pike in deep water, then go with an 8 weight. As usual the rod can be a help or a hindrance. A stiff fast rod would be the best choice (Redington CPS or SS, G. Loomis GLX MLS, Sage Xi2). Rod length should also be considered. A 9 foot rod is a minimum length. Don’t jump too quickly to go with a longer 10 or 11 foot rod – which can be great choices especially when roll casting from a float tube – because the longer lever means more stress on your shoulder and more strength to cast. They also seem to be the extra encouragement fisherman need to try and cast another 20’. Test-cast the rod and get a feel for casting it at a reasonable fishing distance before buying. The reel is of much less importance. Rarely will you ever hear me telling of the importance of a high-end reel. Unless the situation calls for a powerful drag and large capacity as in the case of saltwater or salmon, a basic reel with moderate drag and enough capacity to hold the line is all that is needed.
Often when fishing sinking lines it is necessary to roll cast the line to the surface so that the next cast can be made.  At times it may be necessary to roll cast long distances when fishing sinking lines.
Often when fishing sinking lines it is necessary to roll cast the line to the surface so that the next cast can be made. At times it may be necessary to roll cast long distances when fishing sinking lines.

Fly lines are definitely the most important component for fishing deep. Fly lines to sink deep will come in weights as floating fly lines do. They also come in full sinking lines, where the entire length of the fly lines (usually around 90 feet) sinks, and sink tip where only the tip (5-25 feet) sinks, and the rest of the fly line floats. Sink tip lines also come in interchangeable tips systems. These systems come with 3 sinking tips and 1 floating tip. Each sinking line then comes in different sink rates, rates from intermediate (.5 ips) to type 7 (7.5 ips). It is important to understand that each companies fly lines sink at different rates, there is no standard. The choice of full sinking or sink tip or interchangeable sink tip and what sink rate depends on the depth of the lake and situation.
The full sink is darker in color and the sink tip has the two colors, the lighter green is the floating line and the darker green is the sinking line.
It is apparent in this picture the difference between the full sink and sink tip lines. The full sink is darker in color and the sink tip has the two colors, the lighter green is the floating line and the darker green is the sinking line.

Full sinking lines have the advantage of keeping the fly in the strike zone longer. Since the whole fly line sinks it remains at the desired depth until just before leaving the water. Sink tip lines with short sinking heads have a tendency to pull the fly towards the surface, and are not appropriate for deep water. Interchangeable tip lines are sink tips and can pull the fly toward the surface also, but they also may have a hinging effect when casting. Since the lines have a loop to loop connection where the floating part of the main line is attached to the sinking tip, they can collapse when casting into the wind or for distance. Adding a full sinking line to y our arsenal requires an extra spool for your reel (another reason not to have a $400+ reel when fishing sinking lines as each spool will be about 50% of the reel cost) and can take longer to change as the line needs to be reeled up, the fly removed, the spool changed and replaced, the rod rethreaded, a new fly tied on and more line stripped out. Interchangeable sink tips only require stripping in the line, removing the fly and replacing the sinking portion and retying the fly.  
  Another option is to use sinking poly-leaders. These come in similar sink rates as the fly lines and are available in a variety of lengths. Poly-leaders are the most economical option but have the draw back of being connected with loops and adding to the weight of the line. Adding weight to the line is most problematic. For a brief refresher on fly line/fly rod matching, all fly rods are meant to cast a fly line of a predetermined weight, 140 grains for a 5wt for example and they are tapered to transfer the energy through the fly line with almost total dissipation of energy happening as the loop unrolls toward the tip of the fly line. Adding weight to the end of the line makes it cast awkwardly because of the unusual taper.
Here is a good rod and reel match up. The rod is a 6 weight Redington SS with a fighting butt, and a Redington CD cork disc drag reel.
Here is a good rod and reel match up. The rod is a 6 weight Redington SS with a fighting butt, and a Redington CD cork disc drag reel.

Wow, so now what? With all of these options it depends on your budget and how technical you want to get. For most fly fishers the interchangeable tip line would be the most economical and efficient method. Then add a full fast sinking line to your arsenal for really deep situations. As a final note, you can buy sinking tip material by the foot at many fly shops. It can be a life saver to have 10-20 feet of this in your vest; you never know how it may be used.
Fishing from a pontoon boat can be very effective when fishing sinking lines.
Fishing from a pontoon boat can be very effective when fishing sinking lines. Pontoon boats give you control over your position and allow you to make shorter casts than may be required from land.
Casting Tips
There are a three main keys to casting sinking lines or sink tips: being smooth, casting wider loops, and shooting line.

Being Smooth
Casting sinking or sink tip lines or sinking flies in a herky-jerky manner will end up in lost flies and piling line. With a standard floating line it is possible to stop hard and fast and with a great deal of energy, the fly line is larger in diameter and the energy in the line is not as focused, it also dissipates quickly. Sinking lines are denser, NOT heavier. The weight of the fly line is the same for all fly lines of the same weight class. The difference is they change he diameter to change the density to make them sink or float. Given this fact the sinking fly line carries lots of energy in a smaller diameter and often feels jerky when casting. Be smooth, often it is possible to reduce the power, lengthen the casting stroke and soften the stop. Soften the stop? Those terms may not be entirely accurate from a physics perspective, but they are descriptive. When casting a floating line we try to make the stop over the shortest length possible to transfer the most energy possible. With sinking lines simply make the stop over a longer length (longer time), this will allow for a smoother transfer of energy.

Wide Loops
The loop is the shape of the fly line as it travels through the air. Often as a U-on its side. If we cast sinking lines or flies with super tight loops we will have a recipe for disaster. The sinking lines and flies don’t have as much wind resistance or lift and seem to fall faster. When we cast tight loops the top leg and the bottom leg of the loop are close together and have a greater chance of tangling. Wider loops keep the legs farther apart. So what causes loop shape? Loop shape is the product of the path of the rod tip. If the tip of the rod moves very straight the loop will be very tight, if the tip of the rod moves in a slightly arcing path the loop will be wider, our desired outcome. Another option is to drop the rod tip during and after the stop of the rod, this will pull the loop open.

Shooting Line
Shooting line is defined as the release of the line after the stop, for our purposes to increase the length of line from caster to fly. The first key is to release the line AFTER the stop of the rod. One of the most common mistakes is releasing the line before the stop. The next step is to use the appropriate amount of power for the line being carried the shoot distance. After teaching this for many years I can safely say that most casters get tailing loops when shooting line. Why? The answer is very simple really, to much power. On the final delivery cast, when they plan to shoot, I can see the bicep flex, the shift in body weight and energy to not only cast the line but also throw the entire rod and reel 100’. It is NOT needed. Here is a simple practice exercise. Start with about 10’ of line out of the tip, make a few false casts and release. The trick is to not add any more power than it takes to make the false cast. You already have the energy needed to make a longer cast, just release. Then pick up the amount of line you just shot, cast it a few times, then shoot. Keep this up until you cannot pick up the line anymore.

Actually fishing sinking lines is a little more species specific and will be covered in future articles. In the mean time, practice your casting, and look into sinking lines, scientific anglers website is a great source for more information on specifics about sinking lines!
Author Jeff Wagner teaching casting techniques.
Author Jeff Wagner teaches casting techniques. If you have trouble casting sinking lines or are looking for some extra distance, contact the author about casting instruction.  


© 2022 Jeff Wagner
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