Ginger is a natural antiseptic that kills the fungi that cause dandruff. It inhibits the growth of yeast, stopping flakes, itchiness, and dandruff before they happen. (Source) It reduces inflammation of the scalp as well as treats scalp acne due to its antiseptic properties.
Glass substrate is a sheet glass which makes flat panel displays (FPD), such as liquid crystal televisions (LCD), plasma televisions (PDP), and laptops displays. The ingredients differ from the sheet glass used for windowpanes. Ingredients also differ between liquid crystal and plasma displays.
Substrate is the stuff at the bottom of the tank. Call it gravel which it should not be as normally gravel has a grain size in excess of 4.5mm and for a planted tank you really want to stick with a grain size in the 1-3mm size which is normally what one would call coarse sand.