not sure what these are

[hankstr1]

the picture's kinda fuzzy, but there's little pink "tubes" growing off of the main pink thing.
pink thing

next there's some kind of orange rod growing off a rock. it's pretty solid too.
orange rod

i think this is a sponge or something. it's kind of squishy, but still firm. i got it for 3 bucks cuz it looks all messed up. i'm hoping it will do something though. should i rubberband it to a rock or something or just leave it in the sand?
orange thing

i have these things on a few rocks on my tank, so i imagine they're pretty common. i'm still not sure what it is though. i touched it and it kinda sucked itself in. i swear i've seen it poop though.
thing on rock

and last, i know this is a feather duster (well i'm pretty sure it is...), but does anyone know what kind it is?
duster

thanks to anyone who's able to help me.

 

[Chucker]

haNk, you'll find IDs for 3 of the 5 pics in the Hitchhiker's FAQ mentioned in the forum description.