1. Use a midge tip fly line
A midge tip fly line includes a short intermediate or slow sinking section at the tip end, which helps get your flies down a little bit deeper, and can often give you the edge over others fishing nymphs on a floating fly line.
The original midge tip lines were developed by Rio and had a few feet of clear intermediate line at the tip end. Nowadays, quite a few other fly line manufacturers sell midge tip lines, including Airflo, Cortland and Barrio. I've been using the Barrio Midge Tip for a year or so and it's proved to be a great line.
Based on a similar design to the excellent Barrio Mallard floating line, the Barrio Midge Tip line is easy to cast and works brilliantly for nymphs and buzzers. It's also really well-priced and is a great choice if you want to improve your success when fishing nymphs. The tip on the Barrio is about three-feet, but there's also a Sink Tip version which includes a 10 foot tip for when the fish are down deeper.
2. Watch the loop to detect subtle takes
When you're fishing nymphs it can sometimes be tricky to detect takes. A proven method for improving your bite detection is to hold the rod tip 6-12" above the water surface and watch the loop of line that is hanging beneath. The technique works just like the swing tip method favoured by coarse anglers.
As you're slowly retrieving the flies, watch the loop carefully. If it moves forward or stays forward, instead of dropping back beneath the tip then you've either snagged the bottom or a weed bed, or a fish has taken the fly. Similarly, if you're retrieving and the line drops back, then that's likely to be a sign that a fish has taken a fly and is swimming towards you. A quick lift of the rod when you detect unusual movements in the hanging loop of line should result in a fish attached to the other end.
3. Fish your nymphs with an attractor
Many people who fish nymphs nowadays will fish them in conjunction with an attractor pattern, such as a blob or foam arsed blob (or FAB) on the point of the leader. You don't need to do this all the time, but it can be a very effective way of drawing fish in to your cast.
In many cases the trout won't actually take the attractor and will instead come over to investigate and take one of the more natural nymph patterns you're using. The temptation can be to remove that from your cast and add another natural pattern if fish aren't going for the attractor, but that can often result in fewer fish overall. Of course, like any method, it doesn't work every time, but it can be deadly on its day.
4. Fish the washing line when fish are high up
On those days when the fish are feeding higher up in the water, the washing line method can be extremely effective. This uses a buoyant fly pattern, usually a FAB or booby, on the point and two or three nymphs on the droppers.
The line hangs in an arc between the floating section of your line and the buoyant point fly, which allows you to fish and hold your nymphs in the feeding zone for much longer than most other methods, letting you cover several depths at once.
One extra thing to try with this method is to give the leader a quick tug straight after you've cast. This causes the point fly to make a little splash which can draw in fish for a closer look.
5. Space your flies out well
When fishing nymphs it's a good idea to ensure they're well spaced out on your leader. A typical three fly leader might consist of six feet to the top dropper, a four-foot section to the second dropper and another four-foot section to the point fly. If you're fishing four flies, another four-foot section can go on beneath the lowest fly.
Fluorocarbon leader is worth using, especially on clearer waters. It's denser than copolymer line, less visible to fish and helps them get down to depth faster. There are loads of really good brands on the market - we tend to use Airflo Sightfree G4 most of the time. Riverge Grand Max is also very effective, though has a bit less cushioning than the Airflo line.
6. Remove slack from your cast
When fishing nymphs it's important to keep a direct line and try to stay in contact with the flies. Takes are often, though not always, quite subtle when fishing nymphs. If you've got slack or loose coils between you and the flies then you're unlikely to detect the take in time to strike, and by the time you realise the fish will be gone.
Long leaders bearing multiple nymphs can often be quite hard to turn-over, especially in windy weather. When this happens, the leader will be rolled back over itself with the flies pointing in the wrong direction. After you've cast, give the line a tug or use a 1m long pull. This will ensure any slack line present from your leader's failure to turn-over properly will be removed or reduced, letting you feel any takes far better, particularly if a fish grabs one just after they've landed.
7. Don't go on autopilot
Successful nymph fishing on stillwaters is linked to bite detection and your reactions. It's very easy to get distracted and for your mind to drift, causing you to miss the often subtle line movements that indicate when a fish has taken a fly.
Try to do whatever you can to stay alert and don't go on autopilot. On every cast, try to imagine that a fish is following. That way, it will be less likely to come as a surprise when one takes and you detect a tiny movement in the line.
8. Consider using an indicator
While not everyone likes them, there's no denying that using strike indicators or bungs makes bite detection when fishing nymphs a whole lot easier. There are loads of different types of strike indicator on the market that are well suited to nymphing.
You're not really using the indicator to hold your flies up, as you would with buzzers, so it need not be massive. As long as you can cast it and it helps you detect movement at the end of your line then it's fine to use. One of the smaller polystyrene rugby-ball-shaped indicators is ideal, but yarn indicators like the New Zealand Strike Indicator are also great for nymphing, and a lot easier to cast.
9. Try greasing your leader if it's flat calm
During flat calm conditions when you can clearly see the fly line, you can apply line grease, such as Mucilin or Barrio Line Care, to the butt section of your leader. This effectively extends the amount of line you've got available for bite detection, as you can strike when you see small movements in the leader itself, rather than just the tip of the fly line.
10. React to any movements
As nymphing success relies on your ability to detect bites, you really need to be on the ball and have lightning fast reactions. A momentary hesitation at a movement of the line will likely cost you a fish, so react to any plucks, sways or dips of the line by lifting the rod.
You need not strike really hard, but often the action of lifting will either result in a hooked trout or the sudden deviation in the flies' movements will cause a fish to take right after.
11. Use polarised glasses
As with all types of fly fishing, using polarised glasses is a really good idea. Not only is some kind of protective eyewear essential for protecting your eyes from flies shooting through the air at 100mph, but polarised lenses also aid bite detection by removing glare.
Yellow polarised lenses are ideal on duller days and towards the evening, but darker tints work well when it's brighter. There are loads on the market and they don't need to be hugely expensive to make a difference - though the really expensive ones, like Costas, do certainly seem particularly effective.