Might wanna take out some sand, that way they get more water space... Just keep up on water changes and they should be okay until feb.. I hope.. My baby red is skittish, and my sanchezi just hides behind the heater.. They only been in the tank for 24hrs so they are not adapted to it.. Like he said, most Piranhas are skittsh at a young age, and more you have, the older they get, the less skittish they become.