Hi - you mentioned depth but no other dimensions. Crowding is not a good thing. They do get large and I tend to separate mine out by size as they mature. Put some toilet paper or paper towel rolls in with them as they will search for a dark, "safe" place to spin. I slice my tp rolls in half and line and/or stack them in a corner. If you see one beginning to spin - DO NOT DISTURB IT. even after the cocoon is spun the pupating process goes on inside. By moving them too soon you can disorient the pupating caterpillar which can cause problems with them eclosing from the cocoon. here's a good site with info
lele
silkie rearing
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0.1 veiled - Luna
0.2 green anoles Jaida & Jetta
0.1 brown anole - Jamaica
0.2 house geckos - Gaia & Tia
0.2 felines - Kyndra and Líta