How to connect 3 backwashing systems to (1) 1/2” drain pipe?

[Hyrepower]

I wanted to use a stainless steel half-inch compression line from each system to thread on to a W adapter. So basically three 1/2” male ports into 1/2” female port that would connect to the drain. I planned on using a pex compression adaptor to affix to the 1/2” drain line so I could have the male nipple to then thread on the female end of the hypothetical W adaptor.

Is this a good solution? I can’t find the parts I need. I am using 1 fleck 5600sxt, 1 fleck 5800 and 1 fleck 5810 valve to make this more complicated I need drain adaptors to connect to the half inch stainless lines I intended to use.