I'm not a real big fan of Aragamilk as it often gets as hard as a brick in the bottle and becomes pretty unusable.
I've had fabulous success with Tropic Marin's Biocalcium. It's a powder that I either mix into my make up RO water or add directly to my sump.
Supposedly, it can be added directly to the tank, but I'm a little nervous to do that.
The coralline growth has been rapid in both of my tanks. I have to scrape the front glass every week to get rid of the new growth.
Hope this helps.
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