Planted Tank Enthusiast
Join Date: Jan 2013
Location: Reading, Pennsylvania
Gotcha, then yeah those are okay or if you could find a hardware place that sells almost like landscaping rock, like that go around flower beds, not that NYC has flower beds, but you get the idea. If you can find something like that test the rock with vinegar to see if it fizzes, if it does, DO NOT use that rock it will deteriorate in your aquarium, otherwise if it doesn't fizz soak the rock for a good couple hours, then scrub scrub scrub to get any dirt debris off of the rock them soak some more and repeat. Then let them dry really well just to kill any moss on the rock or what have you, then your ready.
But if you buy from Dr Foster Smith the rock should be pretty good already, I just wanted to give you some info in case you find some without ordering that's what I would do with the rock to make sure it was safe to go in the aquarium.