Before installing the SK5000 Gen1 or Gen2 into the sump you must first install the Float Switch Bracket. The factory float switch bracket included with the Clarisea SK5000 unit will NOT be used with our sump. You will receive 2 different length, white Float Switch brackets with your order from us. The brackets will determine when your roller mat advances. The shorter bracket (80mm) will have a higher water level and the longer one (100mm) will have a shallower level. We recommend starting with the 100mm bracket first if running only 1 SK5000. You will have to experiment with your setup and see which is better for you. There are a lot of factors that influence this such as water level in the sump, GPH Flow thru your sump and sediment levels in your system. Below is a photo of our 80mm float switch bracket installed in the Clarisea.