I have little black balls

[Mudslinger14]

On my live rock that I received yesterday from someone with a tank that was running for a while.

Ive heard it could be bubble algae?
Or some type of sponge

But im not sure...I dont want anything harmful in my tank even before I've put any livestock in it.

 

[Kevin8888]

Well sponges aren't a problem period, technicaly algeas aren't either... but they can spread like wildfire... That said, this doesn't look like any sponge I know of... but I can't ID exactly what this is...

 

[Mudslinger14]

Do you think I should leave it be for the meantime?

 

[Kevin8888]

sometimes its worse to try to remove as then some can spread spores that will create new starts... I would say try to keep the nutrient levels in check, as in regular waterchanges to stop the creation of nitrates so the algae has nothing to feed on.

 

[ar0wan]

..I have little black balls ...

I loled.