Blue Macro - ID Needed

[mjheverly]

Hey everyone,

I've had this stuff growing in my tank for a little while now. It hasn't spread very quickly so I haven't worried too much about it. After just leaving it for a couple months i now have two patches about baseball size in two different areas of my tank. Anybody have an ID for this and whether or not it is something I should worry about?

Thanks

 

[enchelycore808]

Pretty sure that's dictoya. I personally think it's attractive but some find it can be a pest and difficult to eradicate.

 

[tektite]

Yes, its Dictyota. Very invasive and hard to eradicate.