I’m using secondary water so I don’t have anykind of backflow. This is my turn-off. I have this and the valve box, my whole system is underground. Is there a way to hook up the flow meter?
Yes. I’m guessing that is a filter based on the flush valve on the top. In order to get the smoothest flow after the filter, your best bet is to dig up the line 3-5’ down from that box to install the flow meter. It’s small enough to install in a small round box, or a second rectangle like you have there.