I have a new 72 gallon saltwater tank. I recently added 50 lbs of live rock. This is the first thing I have put in the tank. Before I added the rock, my PH was at 8.2, two days later it was at 8.0, obviously my amonia, nitrate and nitrite levels are changing as well. Do I need to add a PH buffer at this point, or will it level off as it continues to cycle? I had a tank a number of years ago, and just started again.

Thanks