Garlic supplement concentrate. Improves appetite. Also contains vitamin C, a powerful antioxidant. GarlicGuard is an all-natural garlic flavor and odor enhancer for freshwater and saltwater fish. Our research has shown that many fish are attracted to natural odors, such as garlic. Simply mix GarlicGuard with any food to attract the interest of fussy eaters like discus and angelfish. GarlicGuard is safe for reef and planted aquariums. 250 ml treats 1000 l.