Something's growing... Is it good or bad??

Ok, so some background information. I purchased a biocube 29 last week and got it setup on Tuesday with live sand from LFS and water I made with RO water from the grocery store and instant ocean aquarium salt. Saturday I added 25lbs live rock I purchased from a forum member who had half in his sump and half in his display tank. Rock was transported home in a bucket of water from his tank. At the same time I added the rock I also added a maxijet 900 powerhead for extra flow. Sunday I added a table shrimp to get the cycle started. The lighting is a retrofit kit from rapidled. Tested for ammonia and nitrate yesterday and today and got the same reading ammonia looks to be about .25ppm and nitrates 0. Good right? Well over night I had something pop up and I'm not sure if it's good or bad. Can someone help identify?
 
Ok, yeah after reading a few threads that seems to be the case. He's very small and at a spot on the rock where I should be able to get rid of him. I kinda poked at him and he retreated into the rock and was barely visible. One forum seemed to recommend dipping that section of rock in boiling water. If that's the best method I think can do that and not harm a large majority of the rock. After finding the aiptasia I frantically searched the tank for anything else suspect and saw this guy growing in a shady spot in a kind of cave I made with the LR. Any ideas on this one? Really hoping for a little better news this time haha

Sorry about the terrible pictures
 
A couple other people mentioned super glue since he's so small so I think I'll try that first as I don't run the risk of harming as much rock. The second picture... I'm being paranoid. Upon further inspection it appears to be a funny shaped rock with some algae growing on it.
 
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