5-8 weeks is a typical timeframe for significant growth. Coralline Algae often first appears as small white or green patches on aquarium glass and live rock before solidifying into a pink or purple hued coating.

When should I expect coralline algae?

What are the Calcium Carbonate levels of your reef tank? These things will help to determine the rate of your Coralline algae growth. However, on average, you can expect to see growth between 4-8 weeks from when you began seeding.

Why is my tank not growing coralline algae?

It sounds like your Nitrates and Phosphates being elevated are probably the problem. As long as your water parameters are good, you should be able to grow Coraline. And Coraline grows slowly. As far as light goes, there are over 1600 different species of Coralline and they respond to different levels of light.