So the cabinet has 3 trays, perfect for having one tray per week. I slide in the newest eggs into the bottom slot, and move them up as new weeks are added. So, if I add the first hatch batch on a Tuesday, then I will continue adding batches on Tuesday, rotating the further along batches towards the top. I don't fill to capacity all at once! My hatcher is actually an older model 1500 with an acrylic door, I just use the bottom of it for hatching because it has an elevated little hatching area at the bottom designed for hatching, but I don't utilize the trays much in the 1500 for hatching unless I need to separate something out. After final candling I usually won't have more than 60 going into lockdown, so the 1500 unit handles it very well. Since you live in a more moist climate than me, I would just open the back vents all the way for decent air flow, and if you worry about humidity, add more water pans.