coraline algae

[u]How to spread Coralline Algae:
Once you have some Coralline Algae you can get it to reprduce by;
Turning off all tank filters and skimmers, leaving any powerheads running
With a single edged razor scrape the existing Coralline off (preferably under a powerhead)
The water current will spread the Coralline throughout the tank where they'll continue to grow. After an hour or so, turn on skimmers and filters.

If you are having a problem with your Coralline disappearing, check your snails, crabs, and urchins. Some of these tend to eat Corallline Algae.