Does anybody Know What This Is???

[Blind River Joe]

Hello:

This is my first post ever so I hope I am going this correctly. A bit of background info first. I have a large reef tank so sometimes I see things in there at night only as would be expected. Just tonight though I saw this animal in my tank and I can not figure out what it is. I have been keeping my salt water reef tank for going on four years now and have had the same 100lbs of live rock since day one. Nothing new has been added in the last 4 months so I don't think I have a hitchhiker from adding new items. The animal is defiantly light sensitive. I have attached a picture and would really appreciate it if some one out there has any ideas as to what this animal may be. The animal is kind of hard too see but if you look closely it is in the picture. It looks a bit like a coral but it defiantly moved just as I took the picture. The animal then disappeared back into the rocks. Look forward to learning new things from all the people out there.

Tank Size 250 Gallons

Lighting 750 watts halogen lighting

Tunze Wave Box

1/4 HP chiller

70 gallon sump

Skimmer

Don't really know what else to say

[monocus]

looks like an anemone,but with it being light sensitive ,it's most likely a worm(Medusa? because of the multiple arms)or some type of peanut worm.it doesn't look like a featherduster

[HollyG]

That's a Majano Anemone. I've had them in my tank and they aren't nearly as difficult to get rid of at Aptasia! I finally decided to get rid of mine because it was getting a good size, but it didn't spread. They most definately can though! They hide during the day and come out at night to try and catch any food particles that go by in the water column. They can move just like any other true anemone, but I found that they only move if there is something seriously bothering/harming them. You can get rid of them easily with Aptasia X. Mine just took a single large dose to die. I would suggest getting rid of it thought since you do know where it is. You don't wan tto leave it for too long then it ends up moving and in such a big tank you may not find it again and suddenly see them popping up everywhere. Better safe than sorry good luck!