Tumbled Slate as BB Substrate?

[reef_noob]

Hi all,
I was at lowes today and found some really cool 2"x2" tumbled slate floor tile and I thought it would make a really cool substrate for my tank which I am switching to BB. I'm not sure, however, whether the tile is fish/invert safe, and also I don't know what type of adhesive to use. Would ordinary tile grout be safe? Would it adhere to glass? If not, what would you use to adhere the tiles and fill the gaps?
thanks,
-Chris

[wharyat]

Well as long as it's not treated with any unwelcome chemicals, it should be fine; also slate is nice and dense our highest tested polyatomic ions will take a while to absorb into it.

As for joining, aragacrete would work for gaps; I wouldn't attach it to the bottom and leave them "floating," but silly cone should work.

[reef_noob]

Thanks, I'm still debating this one. I mean, it would look cool and it would be really unique, but it would be a lot of work as compared to dropping in some starboard. I'll keep the aragacrete in mind if I go for it. I might try doing a square foot and see how easy the process is. If I do it, I'll either have to do it in the tank or do it in sections and place them in the tank when they are finished. I think that doing it in sections may be the way to go because I still have livestock in the main tank and I want to keep the time that the tank is emptied to a minimum.