Odd hitch hiker ID.

[Just John]

Sorry for the poor quality photo. This is about 3mm wide. What could it be?
I am also curious about the brown dots/splotches of algae. There are thousands on the rock.

 

[KingTideCorals]

Sorry for the poor quality photo. This is about 3mm wide. What could it be?
I am also curious about the brown dots/splotches of algae. There are thousands on the rock.

The blob quite possibly could be a pineapple sponge potentally, or some sponge of some sort!

As for the brown splotches seems to be some sort of algae or potentially a bacteria...?

 

[Just John]

No other ideas?

 

[Streetlamp]

Splodges could be cyano do they brush / blow off easily?

 

[Just John]

They don't come off with a turkey baster and snails don't get them. I have a bit of cyano, but it doesn't make dots everywhere. They are all about the same size. It makes all of the rocks look polka dotted.