I'm trying to open my pool myself and I'm co fused about how the in-floor cleaning system I have works. There is a 5 port valve, main equipment pad, and this cannister on the deck that confuses me. At the bottom there is a white pipe and black pipe. The black pipe was plugged and the chamber was filled with antifreeze which I removed. I then uncapped the jet on the wall right next to this chamber and water rushed in from the white pipe. Then I unplugged the black pipe and water was sucked in. There is a basket that sits above those pipes, and then this white fitting with brass insert... is that a plug I need to remove, connected to the main drain? It is very tight and a small space. How does water flow through this chamber and the basket?