<a href=showthread.php?s=&postid=13068870#post13068870 target=_blank>Originally posted</a> by otrlynn
I'm totally confused here. Is the rock you are trying to clean "live"? Has it been kept in saltwater while you were cleaning your tank? If you have been keeping it in saltwater, there is lots of good bacteria that you want to preserve. If you wash it in fresh water of any kind, you will kill all of that beneficial bacteria. If you have been keeping it submerged in saltwater with some circulation you can swish or even scrub the outside with saltwater while preserving the beneficial bacteria. If it has been sitting out of water and is already "dead" you can wash it with fresh water but definitely not at the carwash. They recycle water and it will most likely have crud and detergent in it.