What is this Purple stuff?

[Charles Belisle]

I have recently, started seeing this purple stuff spreading across this rock as quickly as my GSP. Seems they are racing to see who can cover the rock first. Is this stuff bad? If so, should I pull the rock this stuff is on? or is it already dormant on other rocks? Best way to get rid of it? I was hoping that the GSP would just run over it and cover it up. Currently, clean up crew is avoiding it.

Purple stuff above the GSP in pictures. It is hairy. Started out as "Green hair" algae on plug with GSP. has covered about 2" space in about 2 to 3 weeks.

Thanks

 

[Jon Fishman]

If it blows off with a turkey baster it’s cyano. If it can’t come off with a brush, it’s coraline

 

[Gil03]

That appears to be cyanobacteria, not good at all and likely due to excess nutrients in the tank. I'd recommend sucking it out with the hose only portion of your siphon during water changes, it should pull right off the rock like a blanket that way. Keep doing this until you get your tank back in balance and excess nutrient issue taken care of.

 

[kapnkush608]

Coralline algae bruv. It's a good thing, sign that things are going good.

 

[kapnkush608]

Upon further review I see cyano as well the purple hard sturr is good. The soft stuff is bad.

 

[my.PsychReef]

If you are referring to the purple patches then they are coralline algea. Sign of a maturing tank.