I picked up some rocks on my property up north--just because they were pretty. After looking at some in my potted plants for a year or so--and thinking of how pretty they are when wet--AND seeing them used in an aquarium a local pet store (which is now closed)-- I decided to put a couple in my tank. It has been over a year now and I was planning on adding more rocks -- actually making caves since the artifical decorations that I have are now too small for my loaches to hide in (in addition to being just plain ugly now). I got some help identifing the rocks--they are spectacular hematite--typical iron ore from the region.
I have read in this forum that people have found that most rocks leach something into the water. My question is--does anyone know what I should test for to see if these rocks will cause any problems. Has anyone else used these type of rocks?
I have added a picture--yes--it is a terrible picture

Thanks for reading this and for any advice anyone has--
