Bright orange algae on l.r

[larry joe]

What is this orange algae on my L.R...Only a few spots on one piece , closely grouped.....Its very bright and very orange...

 

[greech]

If it's encrusting on the rock, it is probably coraline. Unfortunately, the color won't stick around and it will likely turn purple. I did have some flourescent growths show up on some of my LR in the beginning and that seemed to develop into some red bubble algae. I vacuumed those out and never saw it again.