What kind of green algae?

[snowlynx]

I get the long thin hairy type and now this wider thicker stuff is growing

is it another type of LHA?

it's growing in the sand as well

 

[mcgyvr]

A type of ulva maybe..

 

[snowlynx]

sea lettuce is ok, hopefully not spread

how about this stuff? has branch or structure of a feather

 

[EdgeN]

A type of ulva maybe..

+1

The second & third picture looks like Caulerpa mexicana or something similar to that.

http://www.saltcorner.com/AquariumLibrary/browsespecies.php?CritterID=1984&filter=0