zooxanthellae Transfer beteen Corals


Premium Member
A few months ago I commented on a rainbow Nem that I had purchased as a "RBTA" had yellow coloring showing up. Slowly the yellow has progressed until all new tips have the yellow. Pretty cool, but explainable. Then a small neon orange Nem that had just split and spent a few days hiding decided to take up house next to him. The small orange Nem was pale, but not completely white. Since the little orange Nem had expelled zooxanthellae during his time under the rock he accepted zooxanthellae from the rainbow. His tentacles are now a vibrant tangerine color blending the yellow with the orange he had. I am really baffled by why this Nem accepted the yellow when others have not.

The original rainbow has been moved to the other end of the tank due to crowding and none of the Nems next to him have taken up any yellow.[attachment=1]Rainbow NEM w Yellow.JPG[/attachment]

The Rainbow is a bit washed out in this picture, but you can see that the yellow is lemon in color and the lower tentacle area is more pink and the green at the base is reduced. At night in the blue light he comes into his own.[attachment=0]Nem w Yelow.JPG[/attachment]

The orange Nem is spectacular day or night. The yellow is more tangerine and the lower portions of the tentacles are purple. He has a Halloween look about him. I have been reading everything I can find on zooxanthellae transfer to try and understand why this guy took up the yellow. I have 30 Nems in the tank he certainly had a choice.

Has anyone read any papers on zooxanthellae transfer? I would really like to know what the trigger was for him to accept zooxanthellae from anther "clan" when he had 10 clones in the same area. Side note: All of the orange Nem bubble - tight bubbles and the Rainbows never bubble more than the occasional half bubble . He is not bubbling tight, but I suspect this is due to crowding by the rainbows around him and not the zooxanthellae.