40 lbs of live rock and not one square cm of coralline?!
Anyway, I'm not so sure scrapings in the answer. I gave some fresh scrapings to Deepwater at the fragswap and he's still struggling to maintain patches. He has adequate lighting and a calcium reactor. His corals and fish seem healthy and happy, but yet, no coralline. My 10g has 3 walls completely covered by pink coralline and I've never dosed a supplement in that tank. Heck, I hardly do water changes anymore.
My point is that I don't know the secret to coralline growth. I always thought as long as ALK and calcium were are proper levels and coralline was present, it would jump off! Yet I've seen tanks with calcium reactors barren of the purple stuff. Then Kris' nano which is only a few weeks old, has spots all over the place.
for some reason it won't grow on my rocks at all,
it grows on the glass, and has covered the marina board and any other
plastic thing in the tank, it's a mystery to me?
my algae magnet is totaly pink, lol.