I'm not sure what the yellow things are but I don't think they are a sponge. They actually have an intake tube and and output tube and the LFS had mentioned the name of them when I picked it up but now I can't remeber what they said it was.
I also added 20 lbs of live rock last night and a few more additions to the tank. I added a Flame Angel, a Snowflake eel, another Skunk cleaner shrimp and more snails. I'm not sure who was more stressed out last night, the fish or me. The eel was quite an ordeal. Once I got him in the tank he was stressed big time but seemed to be doing okay. Then I added the Flame and the eel threw up! It was quite a show but I just checked on the tank and everything seems okay right now. I'm hoping that when it gets light out and everyone starts to come out that they will all get along.
I'll post some more pics a bit later on.