aiptasia and a question on another anemone

So tonight I was looking at my live rock in my 10 gallon, and I noticed two aiptasia anemones on one of the original live rocks I had bought. I hadn't seen any since the first three I killed with Aiptasia x, and these 2 just kind of popped up out of nowhere. I took care of one of them, but the other is in a cave, so I'll take care of that one tomorrow. I also have seen another little anemone but it doesn't look anything like aiptasia. This one is kind orangeish and has little white tips on the end of it's tentacles. It seems to only come out at night, and in the light it flattens right out and looks more like part of the rock. Any Ideas what this one might be?
Live rock is so interesting. Different things always popping up out of no where. So far I've seen the Aiptasia, the other anemone, a couple of really small striped snails, a couple of small shrimp, a couple of what look like tube worms (one has a white opening and longer tentacle things, the others are very small and brownish colored), and a peanut worm (weird looking thing...kind of looks like an elephant's trunk with little bristles that come out of it's mouth).