Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
If they are dry then just rinse and use 'em. Rocks in a store have been dry for so long that even if they were from a wet location any disease or parasites have died.
If they came from a wet environment (stream, pond) that is the only time some stronger treatment might be called for. Some fish diseases or parasites might find their way to your tank if the rocks stay wet enough on the trip home.