This is the safest method for making rocks you find in the wild aquarium safe. Using pieces you find in your environment can allow you to completely customize your piece of nature.
It’s a good practice to sterilize anything that may be added to your aquarium to prevent contamination.
Be careful adding materials from the outside. Some rocks (limestone, Texas holey rock just to name two) alter pH of the water. Depending on what you are keeping this could be an desirable (or undesirable) effect.
Immersing rocks in boiling water is dangerous because water trapped within the rock could vaporize. This could cause the rock to explosively rupture.
Pouring boiling water on rocks or driftwood is a safer way to sterilize the outside of the object.
This video provides tips and suggestions on how to sterilize rocks without the use of chemicals (other than dihydrogen monoxide)
DISCLAIMER: I do not take responsibility for your actions or any of the consequences resulting from them.
Music: Skye Cullin by Kevin MacLeod
Track: Skye Cullin
Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0