Lawman,
It says on the purple up bottle that it does not contain any calcium and that you should maintain proper levels of calcium to be successful with the product. Personally, from my experience, I do not add a single thing to my water that I can not measure. I do not add iodine, strontium, magnesium or anything at all to my water. The only thing I add is calcium by a kalkwasser drip.
Hemicross,
Coralline likes low and high light. However, it likes certain spectrums of light. Coralline mainly likes the blue spectrum of light, mostly in the 420nm to 460nm range backed by a 10k light of some sort. Coralline will in my experience not grow under an ordinary shop light with 4k to 6,500k light. (too yellow and not intense).
Kalkwasser is the way that aquarists in Europe have been adding calcium to aquariums for years. Kalkwasser needs to be diluted in water (recommended 2 teaspoons per gallon and no more then 4). The mixture has to sit for 2 to 24 hours before it can be added to the aquarium. Only the clear water on top with the calcium needs to be added slowly to the aquarium. Usually the aquarist will notice more coralline algae groth after 6 months of aquarium maturity.
The more coralline algae, the better. Coralline takes up calcium hydroxide to secrete it around their cells and during the night they secrete a buffer (magnesium something) that keeps the dkh and pH balanced during the day and night.
Have fun growing your algae! If you want to make some money on the side, or perhaps trade for frags, buy some live rock and grow tons of coralline algae on them and trade/sell them and pass along your methods and recipe's. Happy reefing!