I agree. Leave it alone. The only thing you may want to consider is doing water changes to control the ammonia produced from the die-off on the rock. This may increase cycle time, but it could save a lot of benifical bacteria and life on the rock. Prolonged high ammonia levels can kill the visible life on the rock.
Some people are like slinkies...they serve no real purpose yet can still bring a smile to your face when you push them down the stairs!:p
Have a great day! Brian