As part of my routine maintenance regimen, I completely clear out one half of the tank when I vacuum the substrate. Because I use sand substrates, fish waste gets buried easily as the cichlids move sand around. Thus, by removing everything from the tank, it ensures I can see and get to all of the waste. Furthermore, I can vacuum “a little deeper” to get to any buried waste without worrying about stacked rock toppling over. Some aquarists use a sand rake or their fingers to stir up the sand and bring solid waste to the top. I will do this occasionally as well.
Above is a photo of my 55g Mbuna tank before a recent maintenance. It contains lots of Texas holey rock and some river rock, along with some artificial plants. Below is a photo of the same tank after I removed everything on the left side. My Mbuna are pretty messy, so I regularly clear out part of the tank to thoroughly and efficiently clean the sand.