purple_stuff_on_rock

It is red turf algae, get some mexican turbo snails, i got some and they ate my red turf aldae in the first 3 weeks

+1 this stuff will spread all over if there's nothing eating it.

I think it's cyano

im no expert but if it is smooth, id say by the looks of the pic its just coroline algae.

it's cyano. increase flow, do more water changes to drop the trates to 0 and check phosphates.

It isnt coralline because of the bubbles caught by it

Cyano.. Increased flow doesen't help - It's due to poor waterquality or detritus builddup in the exact area. If the last is the case, then flow will help alot.

ohhh i didnt see the bubbles , it all makes sense now

Thanks everyone. I didn't have much flow other than stock so I added more flow and upped my CUC. I removed what I could by hand with water change. I'm going to see how this works and go from there.