RODI Auto Shut Off Upgrade

[Instigate]

I bought the aquatic life 4 stage rodi unit. I'm now kind of regretting the purchase, should have got the brs model I think. I bought the brs auto shut off kit and in the video he says to install the auto shut off valve before the di resin. Is that really necicary? Why can't I just put it on the waste line? Would make it so much easier for me.

 

[Instigate]

Found this,
So I guess I'll do it that way. But still curious why neither of the examples put it on the waste output if anyone knows.

 

[Reefersutherland_]

The red line is b4 the black waste line, so when you shut off at the red no water gets pushed thru the system to the black. The first video explains it