Wiring question

[The New Guy]

Hello, I am new to pools but have reading this and other forums and learning as fast as I can. I am converting to a SWCG. Specifically I am putting in a Hayward AQR15.

My question is around the cleanest way to provide power to the SWCG only when the pump is running. My pump is a VS-3050 and so has it's own timer, but it doesn't look like any power output. As I understand the flow switch for the SWCG is meant as backup. I have seen some references to a relay type thing that senses usage on a power line and turns on your device when that happens, but I haven't found something I can buy. So I think my best option is going to be a digital timer that will run both the pump and the SWCG. I would rather it just start up when I run my pump because then I can vary times and speeds from the pump and be done with it.

Does anyone know more about this mysterious relay device or have any other words of wisdom. Thanks for any ideas, I appreciate this forum.