Shared DWC reservoir, seperate root systems?

I've got a DWC system for my moms and recently removed one mom to make room for a new strain. Don't worry, she went to a good retirement home where she'll live out the rest of her life, which i expect to be about 8-9 weeks. The reservoir is short (~6"), so all the roots hit the bottom and grow into a big mat. All 4 plants had very inter-tangled root systems and i carefully tried to separate them by hand, but inevitably broke some of the roots. The plants seem ok, and I'm adding H2O2 as a preemptive strike against root rot spreading from the dead pieces of root.

Anyways, has anyone found a way for multiple plants to share a reservoir and still keep all the root systems separated so I can swap out plants without hurting the root systems?

I am trying an idea I had to do this with those plastic flexible cutting boards. Im going to X two together to hopefully keep my four site dwc seperated. I picked up a 3 pack at walmart for like 3-4 dollars. I'm gonna leave space for it to rest above the air stones and if needed drill a bunch of small holes so water can still bubble up and move around as freely as possible.

I used some index cards to model out where I'll cut on the plastic sheets. So I took some pics and figure it could help illustrate what I mean better. The lighter represents an air stone.

I would not worry too much about it, I have seen people cut 50% of the roots length... Chop... Straight across... with no ill effects, they actually come bad thicker and healthier. So just chop them off as far down as you can without leaving dead roots intertwined. The H2O2 is also a great idea. Good Luck!

i second dmoose cut them clean , rather than rip them apart, i learned as wat would u prefer, a haircut or ya hair ripped out lol...... i have since done this...........and i prefer a hair cut