red algae vs red laver

red algae and red laver both are nouns.

Word	Noun	Adjective	Verb	Adverb
red algae	Yes	No	No	No
red laver	Yes	No	No	No

As nouns, red laver is a hyponym of red algae; that is, red laver is a word with a more specific, narrower meaning than red algae:

red algae: marine algae in which the chlorophyll is masked by a red or purplish pigment; source of agar and carrageenan
red laver: edible red seaweeds

red algae (noun)	red laver (noun)
marine algae in which the chlorophyll is masked by a red or purplish pigment; source of agar and carrageenan	edible red seaweeds