The crew i paddle with all put a garmin (various models) on the footstrap and can see the arrow perfectly well. Have you tried that?
Zach
Current Skis: Nelo Vanquish AIR, NK 670 double, NK exrcize, Carbonology Feather, Think Jet, Knysna Sonic X
Former Skis: Epic v10g3, Kai Waa Vega, Epic V12 g2, Epic V12 g1, Epic v10 double, Nelo 550 g2, Fenn Elite S, Custom Kayaks Synergy