I have a Coco. Beautiful critters.
They are considered hard to keep because their nutritional requirements are not well known. What I've read is that they will last about 2 years in the home aquarium.
I'm currently feeding my filter feeders a variety of things: Reef Nutrition's Oyster Feast and their live Phyto, along w/ Kent Marine's ZooPlex. From the research I've done, I am unclear as to whether Coco's are carnivorous or herbivorous.
I've tried spot feeding it a variety of things, but that just seems to scare it into its tube. It does curl up around the ZooPlex when I drip it into the tank though.
What I do know is they like moderate flow, and have no lighting requirements (i.e. they're non-photosynthetic.) They also need high quality water w/ in range Ca levels, similar to LPS.
I have mine in a 20gal tank. A 10 may be a bit small, only because the tubes are fairly long. (Mine's almost 10".)
You may also need to take precautions w/ certain shrimp. My Bumblebee was all over the Coco when I first got it (but has since backed off it), and my Cleaner irritates it from time to time. Neither has done any harm to it, but YMMV.
HTH,