Okay, i have seen two of these
nudibranchs crawling around my tank for a while and i am wondering what they might be. Every time i see them, they are on some kind of algae:
Bryopsis (HA), calipura, or other macro. I have never seen them on the red ogo. I checked some books and i think it might be
Elysia Ornata.
I have three pics of them. The pics might all be of the same one or of each, i am really not sure. At one point i did see two at the same time.

__________________
Samuel
"If they but knew it, almost all men in their degree, some time or other, cherish very nearly the same feelings towards the ocean with me.... There is magic in it. Let the most absent-minded men be plunged in his deepest reveries--stand that man on his legs, set his feet a-going, and he will infallibly lead you to water, if water there be in all that region."
Herman Melville,
Moby Dick, Ch. 1.
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