I generally don't grow full trays of anything, but rather 6-cells of this, 8-cells of that, so my trays are all hacked up. Due to the strange size of the shelves I use under my grow lights, my plants don't actually sit in 1020 trays (the shelf is lined with a piece of tarp). I've always just had a tray sitting on the bench with water and would move the seedlings to the tray to be bottom watered, then back to under the lights when they were wet enough. I just keep pouring more water in as needed, and usually only dump it out once a week or so if I need to use a fertilizer dilution instead. Same thing with a larger Rubbermaid wrapping paper tub for bottom watering the longer Speedling tray pieces, which need a fair bit more water to float in. The tub is rather unwieldy to empty so it rarely gets dumped. Is there any reason from a plant hygiene/damping off standpoint to make me change my ways? If I was bottom watering with chamomile tea? I think that's only supposed to be good for a week, but I could certainly use less of it if I'm just topping off the designated tray in the meantime...I'm still losing some plants to damping off even after drastically cutting back on watering and am trying to fine tune my system a bit more since I can't afford to let my newly replanted seed babies end up that way again.