So here's the story, It seems like there are many conflicting opinions on what rocks are "safe for aquarium". in the research I've done it seems that rocks that dissolve in acid (bicarbonates) and tht can be etched with a stainless steel knife are bad.
However, what if a rock is just able to be etched by a knife?
For example, I just ordered some slate Small World Slate & Stone
and on the home page they have an image of a little shrimp on their stone, stone is covered in algae obviously been in use for some time. The video says that they are inert and PH neutral.
However, when I got my shipment these slate pieces are extremely weak and able to be basically etched by a knife no problem.
So what does this mean for a tank then? Are stones that are able to be etched by a knife actually safe for aquarium? Why then does the community say you shouldn't use rocks that are able to be etched?
Wondering what others think, obviously setting stones in water for a week is the most fool-proof test but just wanted to start a discussion on how people came to these testing conclusions and whether they hold up 100% or not.