It was first my colony of green birdsnest, now its the the birds of paradise. White out. A little before work, after work, bed so on. Why. colonies are five years old. Green birdsnest got white leaving one little 1inch stalk
Give us your list of parameters and we might be able to tell you what is wrong, But it's to late for them but can keep the rest of your hard coral from dying if you give us some vital info first!
Salinity and temperature? I know they're basic, but they're also easy to loose track of. It happens to me frequently, and then I wonder why things start to die...