[cokipoint]

I am seeing light green spots on my rocks. Is it possible to get coraline algae after 7wks? I have a miracle mud system with 6 chromis, 1 banded goby and an assortment of snails and crabs plus 2 cleaner shrimp. This is a 150g tank.

[pogodzib]

There is green coralline algae, but it isn't very common in most aquariums. Since your tank is 7 weeks old, it is probably a phase of green algae.

[Bamaguy]

I've got a rock that is encrusted with purple coraline algae but it looks like it is "peeling" off. Will the standard fluroscent bulb (0.5 watts per gallon) grow coraline or should I increase lighting? I want the purple to spread to my other rocks but was waiting to get a bigger fixture for when I bought actual corals.

[pogodzib]

That lighting should grow good, dark colored purple coralline algae, as long as you have some of the darker coralline colors to get started with. The lighter colored purples do better under stronger light. Overall, coralline grows better in low light situations that it does under strong light.