You should keep them in separate small containers for a month or two after you first get them to make sure they are each eating well and are growing before you put them together in the permanent tank. There always seems to be an aggressive, bold one and a shy, clumsy one in any group, in my experience. The quarantine period gives the shy, slow feeder a chance to catch up, and to make sure they are both healthy and active before putting them together. I would remove the clumsy fellow into a quarantine tank for awhile where you can observe him and he has no competition. Some people use a plastic sweater or shoe box, but I prefer a critter keeper with a wet paper towel, a deli-cup of water on its side with a plant leaf such as pothos or a fern frond in it, and maybe a sprig of pilea, curly ivy or such, so the nursery tank isn't barren and the frog can jump behind something to hide. Then seal the vents on the outside with Saran Wrap to insure humidity, leaving only the center feeding lid free. If this has vents, seal them, too. Feed the dusted flies daily and observe the amount eaten, whether the frog continues to "miss" the prey, the consistency of the poop, etc.
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Patty
Pahsimeroi, Idaho
4 D. auratus blue
5 D. galactonotus pumpkin orange splash back
5 D. imitator
6 D. leucomelas
4 D. pumilio Bastimentos
4 D. fantasticus
4 P. terribilis
4 D. reticulatus
4 D. castaneoticus