another Live Rock question
(seems to be the popular topic, so sorry if it's a repeat!)
I have a three year old 45 gallon Fish Only tank, currently home to a grouper, trigger and eel. It's operating on a power head and canister filter, with crushed coral as the base. Currently, all I have are rocks (not live or dead, just plain chunks of rocks/slates) and dead coral. I'm going to upgrade the size of the tank to 75 gallons, and was wondering what impact adding live rock would have on the chemical balance of the water. Currently, all conditions are perfect and in harmony.