Identify please?

[taylor2]

This thing started growing in our tank a few years ago and we have no idea what it is. It resembles purple lettuce...does anyone know what it is??

 

[rhino509]

maybe a lettuce coral.....lol,not being sarcastic,i googled "lettuce coral" and it appears there is a few corals with the nickname lettuce coral.kind of hard to tell by the picture,google it since you can see it the best and see what ya find.
good luck

 

[rustybucket145]

Looks kinda like an algae I had in my 55gal years ago. I bought a yellow tang and within a few weeks the fish had decimated the algae. It was the same purple color as yours and was kinda rubbery in texture. I used to know the name but it's slipping my mind at the moment. It was very slow growing and didn't really seem invasive. Every once in a while a piece would break off and start floating around. I'd just remove the piece and leave the rest to grow.