Rocks/stones For Tank

[jetskidia]

I'm getting fed up with forever replanting my tank after my fish has uprooted them so i'm going to add some more rocks/stones.



Is it possible/safe to buy rocks/stones from places other than fish shops?

 

[piper]

Yes just give them a clean

 

[RadaR]

You have to be careful. Some are composed of materials that will affect the water chemistry (mostly increases the KH which will buffer the pH).
I hear some people doing "the vinegar test". Someone who knows a bit more about could explain in more detail, but I think the principle is if you add vinegar (ethanoic acid) onto the rock and if it fizzes then the acid is reacting with a base (neutralisation reaction). This will indicate that it will affect water quality. You would be better of getting rocks from a fish shop. Not all are boring, check out this link.