Hi,
I'll also add make sure there is no undertank heat on. That will really confuse it.
What size cage do you have it in? If it's too big, it won't feel secure and won't eat.
Sometimes they are just slow starters. After all, mother nature never meant for all of them to survive, we as keepers don't like that though. We've got a couple of basin juvies that just started eating on their own at 9 months.
About the pinkies, ETBs will NOT eat pinkies on their own as first meals. They do not give off enough heat to attract. You must feed hopper mice that are big enough to move around and give off enough heat to excite the ETB.
Good luck
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Karen Clark
Gems of the Rainforest