Thank you all for your advice! It was from a friend's tank who grows them (green & pink) like weeds . Embarrassed to admit I don't acclimate stuff from him like I do from stores since he helped me set my tank up and we have similar setups/parameters/and use same additives (my bad, I know).Big difference is I have a much better skimmer (G3), my tank is taller and he runs t5&Led. This stuff came from top of his tank. I started out at the bottom, and in 2 weeks the green turned white (pink fine).Got another (this one) and same thing.Now I have another piece I am trying at top. 2 things I have a problem with red turf algae and almost all my Palys turned white?? Zoas started shriveling up. Don't know why? No pests or pox that I can find on them other than turf algae.