coralline algae?

I noticed purple dots growing on a piece of live rock the other day, and assumed it was coralline algae. A couple of those dots now seem to be growing UP. Is it coralline?

 

I'm curious to know as well, as I have it on my rocks as well.

 

Looks like coralline to me. If i'm not mistaken coralline can develop crusts of various thickness and knob like purple bulbs are not uncommon. They also tend to start in small circular formations. How old is the tank?

 

3 weeks

 

3 weeks is a bit young to be developing coraline unless you used water from an established tank.

 

That looks like Foraminiferans.

Take a look at this link and scroll down to the forams and see if that looks similar at all.

http://www.lionfishlair.com/hitchhiker/hitchhiker.shtml

 

Renee has it correct.

 

i thought that three weeks was a bit early for coralline too, thats why I asked Thanks for the article Renee, that is so awesome! I noticed them around week 1 in or so, and now they are all over the place. I honestly thought it was just my imagination for awhile there lol. This is such a great hobby. I wonder now what I did before...