The spirals are really tight and small.

Whatever you use to tell you the moment when a fish has inhaled your nymphs, indicators are essential for consistent and successful nymphing.
Delivered to me this week was the Hanak Competition Czech Nymph Micro Spiral Indicator. Made from bi-coloured monofilament, it is yellow blending into red. The colour change being exactly in the middle of the spiral. Stating 40cm on the information, it is actually 45cm, with the spiral being some 2cm in length before being stretched.

The ends of the nylon are left free - this allows you to choose how you incorporate it into you leader. Perhaps a blood knot or water knot may suit you. My preference was to tie a 2mm ring to each end.

A successful indicator must meet the following brief in my view:
1) Easily visible from distance and in different light conditions
2) Doesn't tangle and requires little maintenance
3) Doesn't interfere with the tip guide
4) Is sensitive enough to detect the most subtle of takes
5) Durable

My concern when attaching this leader was whether, after some casting and hopefully hooking a few fish, it would straighten too much and be rendered useless.

When a fish is hooked, the spiral indicators will straighten. It's really important that the coils return quickly and do not tangle. So how about this one? Pulling the spiral and making the indicator completely straight required a little tension. This was certainly sensitive. But when I let go, the coils sprang back into shape and no sign of any tangle. Perfect!

It was a sunny day. The varied light on the water would certainly test the indicator. So, with and 10' 4" #3 rod set up, the indicator placed about 6' above my point fly and a dropper of a couple of inches, I was ready to really test its effectivenss. As I started making a few casts, the spiral indicator was easily visible, whether the background was bright reflected light of darker shadows.
When the nymphs touched the bottom, the indicator opened. Getting into a casting rhythm and searching the water with a Pheasant tail on the point, it wasn't long before the indicator twitched and stretched open.

A small grayling came bouncing to hand. Three casts later the spiral widened and a quick flick of the rod was met by the thump of a better grayling. The spiral indicator was certainly doing its job ~ and well.

So after a couple of hours' fishing, how did the indicator fair?

Detecting takes was simple and effective. It's very sensitive and allows you to pick up on even the smallest of interuptions of your fly. You can even sense when the current changes - just slight adjustments in the spirals.
Sure, it does stretch and the spiral widens and lengthens during fishing. The spiral length was about 6cm and 3mm in diameter by the end. But that is perfect for me and certainly didn't upset the effectiveness of bite indication.

So an impressive product. Certainly when faced with delicate takes these will help you make contact with the fish. Useful for Czech style nymphing and the longer leader French nymphing, this is a useful tool.

Highly recommended: the Hanak Competition Czech Nymph Micro Spiral Indicator

~Dave