My panther geckos are half the size of my crested gecko. When I let my crested out of his cage and crawl around the room, he usually climbs all over the other geckos cages first. When the crested gets near my male pictus/panther gecko's, the male pictus puffs himself up and does some territorial display, like he is doing push ups and puffing his neck out. Meanwhile the crested barely noticed and just continued to climb on. So obviously the smaller panther feels threatened by the much bigger crested gecko. That alone tells me that it would not be wise to put them in the same enclosure, not to mention completely different habitat requirements. The rule of thumb is one animal per enclosure, even if it is of the same species.