Does anyone know what these are?

[smeac72]

These came on the live rock. Looks like two mini alien eggs. Kept looking at it without any change for about a month, but today they are no longer smooth but looks like tiny bumps on them and something came out of the top of one and fell to the gravel in the bottom of tank. This rock also has some worms that I haven't been able to id. Uploading pic of "eggs" is this something good or bad?

 

[meowzer]

Looks like sycon sponge....also called q-tip or pineapple sponge
harmless filter feeders will come and go

 

[smeac72]

thanks for the response. I am amazed at the life found in the live rocks. Still trying to figure out what the different crabs, worms and other crawling things are? Do these sponges multiply?

 

[meowzer]

They will depending on nutrients.....most of the time you will find them in caves or out of the way places
YES...Watching and seeing allthe "new" life is amazing....and no matter how long you have the tank....it never ceases to be that way