Troutline Tactical Jan's New Deep Dark Olive Gammarus BL Nymph is the updated version of the previous olive scud. These scuds are highly efficient on rivers with low waters and where is plenty of green algae and watergrass.
If is not raining for many days then algae are developing fast on the river bottom. Those brown, reddish and green algae are the best place for olive scuds. When these conditions are met, olive scuds will do their job!