I have seen a lot of coralline growth over the last few months in my 10 gallon. My parameters over the past 6 months have been roughly:

temp 80-81
sg 1.024-1.025
calcium 450-475
dKH 10-11
pH 8.2-8.3

I have a little bit of the green, some red, and tons of the pink/purple! It's been exciting watching the changes!

Below are some pics for comparison...