Answer: alga

AnswerCrossword Clue
ALGAOyster thief or mermaid's wineglass, e.g.
ALGAAquatic eukaryote
ALGABit of plankton
ALGAKelp or plankton
ALGAPlankton component
ALGARootless plant
ALGAKelp, e.g.
ALGAOne-celled plant
ALGAChlorophyll-containing organism
ALGAComponent of a lichen
ALGAPhycological unit
ALGAKelp, for one
ALGAPhotosynthesizing aquarium denizen
ALGAMarine plant
ALGASeaweed, e.g.
ALGAStagnant water problem
ALGABit of pond vegetation
ALGAPond plant
ALGAStagnant water growth
ALGATiny pond plant
algaseaweed (a plant growing in the sea)
ALGAWater plant
ALGABirdbath organism
ALGAGiant kelp, for one
ALGASimple plant
ALGAKelp is one
ALGAKelp, for example
ALGAPond floater
ALGAAquatic organism
ALGAPond growth
ALGASeaweed
ALGAAquatic plant
ALGAHalf a lichen
ALGAPond life
ALGAA real piece of scum
ALGAPond organism
ALGAPrimitive plant
ALGASea growth
ALGALichen component
ALGAFragment of pond scum