Biodegradeable strike indicator putty developed and patented by Loon Outdoors.  One-Third the density of water, Biostrike floats high and won't become waterlogged.  The putty is very moldable when warm, but hardens and adheres securely when it hits cold water.  You can easily add or subtract Biostrike to adapt to changing conditons.  Biostrike is also reusable, so a tub lasts a long time.
Available in:
Hot pink,
Yellow
Orange,
and a 50/50 combination of yellow/hot pink
1oz tub

Price: $10.98