how 2 test rocks?

[Doby_the_Dojo]

ok how do u test rocks to see if they are ok in an aquarium? i had some in my turtle tank for awhile (from the lake) they've been there for like a year i wuz just wondering if theyd be ok with my fish... i wuz thinking that u put white vinegar on them but im not sure... and if so i don't know how to do this or wut to look for Thanx for all ur help!

 

[Changes-In-Latitude]

If, after dropping a little vinegar on them, the rocks fizz or foam (like when you add vinegar to baking soda) then they shouldn't go in the tank. Another way to test the rocks is to fill a container with water and let it sit for a day or two. Test for pH. Then add the rocks and let them sit in there for a couple weeks. Test the pH every few days to see if there is significant change.
HTH