Can Someone id this algae for me?

[Trefaca]

Considering that the live rock came from the Caribbean and the red seaweed feels geleteous and is slippery to the touch; Halamenia is most likely.

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Know this: Halymenia species are often called Dragons Breath/Dragons Tongue/Red Sea Lettuce

Perhaps if you took a picture of both red seaweeds in LFS that sold you the rock. Then we might move past generic names.

Who knows, the LFS may have two seperate species of Halymenia.

Great idea I will do that next time I'm there. Thanks