[Tangster]

What type of sand did you use on the bottom ? where are your Levels of Ca. DKH and Magnesium setting at ? The skimmer is a bad idea as it will remove the free floating coralline spores and as for the Cyano ? Its not an algae its an anaerobic bacteria and what you see is the little covering it produces to protect its self from oxygen. if you increase water flows to the bottom of the tank and increase dissolved oxygen to the system that will help to brake it down. Or you can just use some type of antibiotic to kill it also tetracycline is the best I found to use.

Cyano's also does not like higher Carbonate and Ca levels. But corallines do .. And you may be adding to the problem with over feeding and that exhaust the Carbonates also .

If you used a good aragonite bottom cover did you rinse it well as the people will tell you to do ? If so that mistake number one.. All the dust that was washed out was just what is sold as Purple up and glycerin in a bottle , As for kick starting coralline growth.. And you really needed to add a shot of good coralline encrusted rubble rather then a rock with some it . .

Also new growth of coralline does not like light and then if you add light just use actinic not white .. that will retard its getting started also take that rock you have and cut the skimmer off get the levels of Ca Carbonates and Mag up and cut the main pump and stop the skimming for a few months and scrape that rock and let the scrapings to settle out for a hr or so then cut the main pump back on and not the skimmer it will come..

So at the end of the Day coralline algae needs the same water parameters as any of its higher evolved cousins that we call SPS , LPS and all corals . Thats what coralline algae is a old coral the first coral to appear and Thats why I never add corals until I see them as they are a great barometer of the proper water conditions for their cousins ..This is why so many have a problem getting the coralline's to start growing.