Can anyone tell me what this is? pic included.

[rufotattoo]

i just noticed this thing black with white tentacles growing out on it and only my Sally Lightfoot Crab was lurking at that spot, i also just started my salt water tank not to long ago, any info would be appreciated. i guess its either a sponge or some kind of anemone i can be wrong thou. thanks.
IMG_0358.jpg

[Fancyfish]

could it be eggs?

[rufotattoo]

i went and showed it to the fish keeper at the pet store he thinks its an anemone, well ill just wait to see if it grows and if it is really one, i found out there is an black anemone that they used to have perhaps this is it...

[rage]

Look like a majano anenome. Bad news, those guys could spread and take over your tank.

[johnnymisty]

Ya majanos are bad news nuke him quick I got one in my tank and he spilt a thousand times already been killing them with aptasia x with no problems

[nacra99]

looks like a majano! You really need to kill it before it reproduces... it can engulf an entire tank very quickly
Any commercial aptasia killer should do the trick.
Or if you don't want to use chems.. you could...
1) Take that rock out use a turkey baster to squirt some boiling water at it while trying to avoid the rest of the live rock. That should kill it but there may be some collateral damage.

2) Take out the rock and partially submerge it in a bowl or tupperware while keeping the anemone clear above the water. Pour a heaping tablespoonful of salt on it and let it sit for an hour or so.... Afterward, just quickly rinse the salt off using the water in the bowl and back into tank.

[makatak123]

You have a pest that all aquarists hate! I killed mine the cheap way lemon juice and a syringe. Fast and easy!