Neon orange turns to red. Time is what creates the coraline, Patients is the key to everything saltwater.
You are not going to hurry anything up adding stuff to the tank, too much purple up will send the calcium off the charts. If you are using it make sure to test the calcium levels. Too much calcium will hinder growth as well. It grows when water is good.
Proper PH and the right numbers in calcium will cause the coraline algae to grow faster. So instead of trying to grow coraline, concentrate on perfect water...then all good things happen.