Best Way to Seed Coraline Algae

I actually like the look of coralline algae. I also started with dry rock about a year ago. I have now got coralline algae growing on my back glass and it grows on my pumps and stuff. As long as you keep your viewing glass clean every week and you do monthly maintenance on your circulation pumps, you will not be having to scrape it to much.

 

As other have said, a few pieces of rock with some coraline on it will do the trick.
Many of the LFS near me have a rubble bin in their live rock tanks. I like to dig through that rubble and find small pieces with different colors of coralline. I've found purple, red, pink and even a pail green. As it begins to spread it makes for nice mix of color.

 

Coral covered rock is preferred over coralline covered rock IMO. You don't need coralline to have a healthy successful tank.