can anyone tell me what this is????

[wicked6921]

ok so one one our live rock in the tank it this weird white stuff kinda looks like feathers up close. its soft to the touch........
heres a picture

[LeslieH]

It's a sponge.

[LeslieH]

One of the very many different shapes of sponges.

[wicked6921]

its upside down in the dark under a rock are you sure it is a sponge?

[LeslieH]

that's a common habitat for many sponges. They're not photosynethic like most corals and don't require light. They're vunerable to predators especially the ones that can tolerate the sponges chemical & physical defenses. the species found under rocks or in other inaccessible areas tend to have less protection than the more conspicuous ones.