My Real Reef Rock is covered by... lime green algae

[peterf]

Hello everybody! I've kept fowlr tank for about 3 months using Real Reef Rock. Excellent water conditions: nitrate 0ppm, phosphate 0.03ppm, seachem reef salt, using caribsea purple up and api marine algaefix, white and blue led. Is this algae green coralline? If so will they turn pink or purple? Has anybody got purple algae on real reef rock? Thanks