Moving 'patashio Nut' Looking Creature

[westiemarble]

Hi, I'm a newbie to both the marine and forum worlds - so here goes.

I set up a 12g nano tank with 7.5Kg (16.5lbs) of LR and 9Kg (20lbs) of LS only 5 days ago and am now waiting for the tank to cycle. Even though there's nothing much to see at this stage I find myself constantly staring into the tank. I seem to gain more feather dusters each day and have a few other plant type things as well. However, last night I spotted a bristle worm and then a moving 'Pastashio nut'!

Obviously it wasn't a patashio nut but a creature on the sand and hard against a little bay in the LR. The shell was slightly open at one end but this would occasionally snap shut before opening again. The creature appeared to be trying to get at something on the LR and rocked from side to side in doing so. The bristle worm soon disappeared and the 'nut' just stayed against the LR. This morning the patshio was gone and I can't see him anywhere. Just wondered if anyone knew what my little pet could be? Cheers.

 

[CageUK]

I've a couple of these in my tanks. I've no hard and fast id but they are some kind of muscle like bivalve mollusc. They apparently bury themselves into the live rock but don't do any harm. They are good guys.

Cheers

 

[1entra]

Your mysterious creature sounds like a barnacle or a mollusc. Here is a good link for hitchhikers:

Hitchhiker website

 

[SkiFletch]

Tough to say without a pic, but sounds like a peanut worm...?

 

[westiemarble]

Thanks all. I think it is a Bi-valve mollusc and would love to take a picture but it is hidden somewhere for now.

As my tank has just started to cycle does anyone know whether this creature will survive long term?

Cheers.

 

[CageUK]

Mine got through a short and relatively benign cycle but I see no reason why it wouldn't make it. Just wait and see I suppose (not that you have a choice!).

They do seem to secret themselves into a nook in the rocks and rarely if ever wander out. If you are lucky enough that it beds itself within view then you'll have a critter to watch, if not you will never seem him.

I stumbled upon one as I was cleaning out my D&D that I had forgotten was in there.

Also if you are lucky you will see it extend it's 'foot' to move around but as I say for the most part they stay fairly static.

Cheers