I've noticed that they prefer eating coraline off the rocks than the glass/acrylic.
Yes, they seem to prefer coraline over other kinds of algae.
Best of luck,
Roy
[quote author=sfsuphysics link=topic=4222.msg50822#msg50822 date=1217704497]
How big is your tank? I have 2 in my 100g tank, and I have the feeling they're the reason coraline algae doesn't grow on my rocks much at all yet grows like crazy all over the acrylic. Also one in my 120g soft tank, same deal there, except that tank has corals growing on most surfaces so not a big deal.
So yeah they might seem small, but they do get around and can eat.
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