Making Rock Out of Cement

[ca1ore]

Thinking about making some reef bases out of concrete. Did this a long time ago (white Portland cement, reef sand/crushed coral and some rock salt); I let the structures cure in humid air and then soaked for 3-4 months. Any new thinking and/or recent experiences I should consider?

 

[Js.Aqua.Project]

I did this a couple years ago, no negative effects that I saw on the tank.