Coralline not growing

[IslandReefer]

If you don't have a lot of coraline an urchin will definately strip what you have and IF you arn't growing any he will starve and you will have little coraline. My tuxedo carves a 1cm trail about 10ft per day right down to the white rock or glass...I have lots of coraline so it grow back quick and I like the cycle......coraline ....urchin poop....to more coraline.
Two methods of increasing coraline growth in a reef tanks, that I have come across are:
1) Take a good size powerhead and place it, up close and personal, blast a heavily encrusted rock continually untill desired purple is reached
2) Scrape the coraline off some of the back glass (or wherever you can get it), pulverize it and, either , in a fine net bag, placed in a high flow area or turn off your flow and sprinkle all over and let settle...season to taste
I have also noticed that different color coralines dominate different surfaces and light levels .
IMHE Good Luck