Purple Up does not contain coralline algae. Some living coralline algae must already be living on rocks or aquarium glass.
High dissolved phosphate levels inhibit the growth of coralline algae (and corals) and favors the growth of nuisance algaes. Check phosphate levels and use Phos-buster or other products to lower phosphate levels if necessary.
Carbonate harness levels should be maintained at natural seawater levels 2-2.5 meg/L or higher.
High nitrogeneous waste levels encourage nuisance algae growth, keep nitrogenous wast levels in check.
Keep pH in the range of normal seawater (8.2)
Light spectrum in the range of 5500K or higher favors the growth of coralline algae.
Grazing animals such as snails, tangs, and reef friendly hermit crabs encourage coralline algae by consuming competing fast growing nuisance algaes.
Coralline algaes have a life cycle that determines the speed of formation of new colonies. Different species of coralline algaes may grow at different rates. It is not unusual to take several months for pink and purple coralline algaes to reach rapid growth rates.