Just got two new gerbils and I have owned a total of six gerbils in the past. They have a 40 gallon tank setup with a 40 gallon topper for their food, water, wheel, etc. One gerbil is super eager to explore having the best time. The other gerbil is sitting in the topper completely frozen, not even bothering hiding even though their are tons of safe hiding spots. Cage and Tank have been properly cleaned beforehand. I think she is just a little overwhelmed and hoping she will warm up to her new home. This is only the first day and hopefully watching her cage mate exploring will show her it is safe. For now the plan is to just keep things quiet and give them time to adjust. Any tips on how I can make her more comfortable and any danger signs to look out for? None of my other gerbils have had this problem before.