Hi all! Getting back into chickens after 3-4 years without. I am buying 18 standard sized straight-run chicks that were born last week. Their first "home" is gonna be a Tupperware container 42" X 20" X 15" deep with a screen top. About how long (your best guess) will this be suitable for them? IOW, how long do I have to get a proper coop? It's been so long since I had chicks I've forgotten how quickly they grow up.