I've read a lot of conflicting info in this. One article recorded 3 cups of play sand leaching 17ppm silicate into a gallon of saltwater in a couple days. Others say it is has been used over and over with good results.

Has anyone tried this? And what levels should the silicates be at anyway?

ive used it in freshwater, would i use it in a salt tank? hell no! im pretty close to just runnin bare bottom because it seems like i have more problems from substrates than benefits

Oh, meant to say conflicting.

Fixed it.

There was a large debate on this 6 months ago do a search and it should pop up.It was 10 pages deep. I have been to the plant where they bag play sand (oldcastle) and I wouldn't even put that sand in a sandbox.