Food chain illustrates how one organism is eaten by another. It also gives you an insight of the movement of energy from one organism to the next. It starts from a producer to primary consumer to secondary consumer to tertiary consumer. Producers are plants or bacteria. Primary consumers can be either herbivores or omnivores. Secondary consumers are either omnivores or carnivores. Tertiary consumers are usually carnivores.
Among the given options, the producers are water lilies, algae, cyanobacteria, duck potato, mosquito fern/fairy moss, and duckweeds.
Among the given options, the primary consumers are ducks, geese, fish, water snails, turtles, earthworms, frogs, pond skaters, and water beetles.
Among the given options, the secondary and/or tertiary consumers are ducks, geese, fish, frogs, dragonflies, water beetles, newts, water snake, and salamander.
To create a food chain, start first with the producers, then the primary consumers, then the secondary consumers, then the tertiary consumers, all of which are encompassed by the decomposers and detritivores.
FOOD CHAIN #1: Duckweeds (producer) ---> Ducks (primary consumer/omnivore