Why isn't my coraline algae growing!

[Timbits]

Hey Dan,

I did some research last night and found the exact same products too! Whew! I think im going to try the poly-filter, sounds like a great product that can remove other things as well like phosphates. Id be interested to see your results from your test! Maybe we can both post our results here. Ill keep you posted!

I might still change out my rocks though, I have a feeling that maybe the rock is too saturated with the Cu, thats why im not getting any coraline on it. and maybe even if i can remove the Cu with those products, the rock is still too damaged to be able have coraline grow on it.....
What do you think?