We often get asked by customers how to install their sand filter so that the MPV connections to their pump and to their return line (usually chlorinator cell) line are correct. The products come with manuals but one thing customers don’t find explained in the manuals is the direction to plumb them in. There is often tiny printing next to the outlet but that is very difficult to see for most people so I am putting some photos below to show you.
You can see the higher outlet coming in from the pool pump and the lower one plumbed to the return line, there is often where a salt cell electrode is installed
https://davey.com.au/media/custom/upload/13779-6_Crystal_Clear_Media_Filter.pdf