I have to ask why you say the hides have to be identical. I have a larger tank and so I have six hides in it. .... Lets see two identical rock hides, two identical small rodent hides, a over turned cereal bowl that has a entry cut out, and a half log..... Now most the time he will hang out in one of the two rock hides, then the majority of the time after that he hangs out in the over turned bowl, and if he just ate he likes to hang out under the half log...... He very rarely uses the small rodent hides, and will ocasionally hang out under the bushes that are in his tank..... He still has not chosen to use the matching rock hide......