Reflective or Fluorescent Tape

This is the type of material you see on traffic cones, or as patches on safety clothing. Available in many colours; silver, red and yellow being the most popular. If you buy it from an angling shop it will normally be self adhesive.

One strip can do a number of rods. Cut a piece wide enough to just wrap around the tip and about 6″ long. A good tip is to shine your light just off the tape so that it reflects the light cleanly without looking like a fluorescent tube. As an alternative you could whip the top 6″ of the tip with fluorescent thread.