Rocks are a great way to add character to an aquarium, but you need to make sure what you are putting in is safe for your tank. Cleaning them is exactly right. Make sure you scrub and rinse any possible residue from the rocks.Try to identify the rocks and then check what, if anything, they may leech into the water. If you post pix , some folks may be able to help ID them and give you tips on how to clean that specific rock. Once identified, it should be a snap to determine if they are water safe
Does anyone know if "plain" rocks they would harm any corals or
live rock that might go into the tank?