Can you get addicted to live rock???

[SWMWTHDAFISHES]

OK, so in the scheme of things, I have been in this hobby for the equivalent of about a minute and I think I'm completely addicted!!! I think a saltwater tank should be as standard in every house as a refrigerator!!! I am on week 5 of my tank cycling and have 30 lbs of live rock in my tank. Who would have thought that 5 little pieces of rock could be so fascinating???

OK, on to my question. There is something living in one of the rocks that looks sort of like an anemone as far as tentacles are concerned. Bear with me on the description b/c I am totally guessing at this stuff, but hopefully you guys will know what I'm talking about. This thing is actually inside of the rock (I'm guessing). I see one spot in the rock where very thin tentacles seem to come out and sort of feel around on the rock. They are very, very thin and at first I thought it was the current moving some sort of stringy slime, but no, it's moving by itself. This has been perplexing me for a while, especially when I see the occassional discharge of unwanted matter from the vacinity of that hole. Well, today, I saw a tentacle just like the small ones that came out a little farther down from that hole on the rock. It was feeling around and because it was bigger, I could see particles actually passing through it (it's like a frost color), almost like it was swallowing (I bet it probably was). Does anyone know what this is? I'm so new at this, it's probably just a common hitchhiker and maybe even an unwanted, but I think it's just so cool! The tentacles look very long and just spread out, feeling around, but I can't see any actual base b/c it's inside of the rock, I think. The tentacles are so long, almost looking like long strands of long hair laying around on the rock.

Anyone know?

 

[Great Lakes]

Welcome to a fascinating hobby.

IT is hard to accurately guess what you may have. Cold be feather dusters, tube worms, etc.

Sadly, there is one creature that often comes on live rock that is unwanted. It also fits your description. It is an aiptasia. A form of anemone that is considered the weed of the reef world. It will sting corals and can reproduce at alarming levels.

Here is a decent picture.

GL

 

[Navarre]

Sounds like Aiptasia or a Tube worm as Great lakes has mentioned.

As an alternative however it "might" be a small brittlestar. Small ones have a habit of wedging themselves into the rocjs and allowing themselves to grow too large to ever get back out. They then send out 1 or 2 tenticles to search for food. This way they are much safer, if a fish or other predator attacks then it will only get a few tenticles, the brittlestar can easily grow these back anf it still has other tenticles inside the rock that it can use for foraging whlst its severed ones are regrowing