Fixed height. Being able to adjust light distance per tray is better when you have different height plants on a single shelf. It’s also less work when building it.
In my setup I have my lights on chains that I can raise or lower. It’s honestly a pain. I end up just slipping a couple 2x4 pieces under the trays rather than bothering to move the lights.
Is the height of the lights adjustable or is that what you’re using the bins for to raise the plants instead?
Fixed height. Being able to adjust light distance per tray is better when you have different height plants on a single shelf. It’s also less work when building it.
In my setup I have my lights on chains that I can raise or lower. It’s honestly a pain. I end up just slipping a couple 2x4 pieces under the trays rather than bothering to move the lights.