I broke up some slate and used the pieces to sort of build a little house shape. The slate started life as a 3/8 thick piece of natural slate floor tile. I stuck it together with aquarium silicone and let it cure almost a week before all the odor was gone.The fish love it. Sorry about the picture quality.
Oh Ok someone said to just start stacking and it would make little nooks and crannies and I was just thinking... You nut how would that work, but now I get it. Lol. Thanks!