unsure of something on my coral - new tank owner

[bcshepard]

I have a new tank I setup earlier this month. I used all water from a trustable store that knows what they are dealing with not someplace like ***** (IE saltwater specific outlet) local here in vancouver WA. Everything is going good. I specifically ordered a porcupine puffer fish. In with his about 8 other fishies an an army of crabs and snails that he is making a good time at going through. So far 0 aggression to fish. I chose for now some cheaper fish that will look nice in a larger tank I plan to build for him when he grows a little bigger and seeing if he plays cool with other fish before I look at investing in other fish before going for more expensive items. I have 4 clowns and some damsels etc.
Anyways. I was feeding the fish and crab army today and noticed on the side of my rock something odd. Something about the side of a snail but obviously not a snail. Stuck my hand in and felt it. somewhat fleshy. I'm taking a guess this is something growing but what I'm not sure so looking for pointers. About 2 inches to the side of the snail. You'll see some misc food still in the tank.. All that gets eaten by my crabs in about 2 minutes when it hits the sand bed.. there's quite a few down there.

 

[eric b 125]

sponge is my guess

 

[1guydude]

Hey im from Wa as well.....or are u on the canada side? anywho yes i would say sponge most likely! Welcome to the site shephard

 

[mr. limpid]

I also say sponge, one of many items that will grow out of your rock. Just sit back and enjoy the show.I hope you are not planning on adding the other 8 fish right away, if your tank is a month old not done with cycling yet.

 

[bcshepard]

I used live sands, carted a truck full of jugs of water from already established water. Add to that the bacteria from the live rock it was a pretty good jump start. I've been keeping a very close eye on things so far. So far my little crab army is keeping my puffers dirty eating habbits at bay but he eats a lot of the crabs. Interesting little fish.
I would like a dwarf lion fish in the future maybe when I get a 90G currently I have started in a 50G collumn. However I am just a tad worried about the puffer and the lionfish not sure on this compatibility. So far my puffer has shown 0 interest in other fish around him no aggression or curiousity but things have just started.