Just thinking out loud here, but are you sure you want your tubs 100% air tight?
You need some fresh air exchange in the chamber to help aerate the droplets, plus the roots need O2.
Atomizer talked about that at one point. When he was using air tight, rigid foam to build chambers, they needed a way for air to get in and out. He said it was typically the drain pipe, and leaks around the net pot that provided the air exchange, but that those same air leaks around the net pot could cause air pruning of the roots. The air flow being too concentrated, and drying out the roots locally.
He switched to the fabric chambers partly for better air flow that didnt cause air pruning, and partly for the evaporative cooling effect. The fabric pots Im using let air through easily, and you can see light through the fabric. Thats why I had to build a light shield around the chamber from rigid foam. The cooling works so well, I had to put a heater inside to keep the temps up in a good range. I left small openings in the rigid foam light shield so air could get in/out, but made sure they were in places where there was no light - the back of the area under my work bench.
Your tubs would be the equivalent to a soil grow with a solid plastic pot to grow in vrs an air pot or fabric pot. One lets the roots get plenty of O2 and one doesnt.
Might be something to consider.