I've been keeping marine tanks for 6 years now and I've never had as much as a spec of Coraline algae grow in my systems. I started my first reef tank in January, and I thought the additional ca/alk/mg & etc would finally result in Coraline growth, but still 0. The only way I've introduced it is via rock/shells. Tank is a 30g AIO, light is an AI prime 16hd with par around 80-130 trhoughout, only using RODI water & changed the filters before setting up this tank. Any idea why it isn't spreading?