Depends on the size of the enclosure and the relative sizes of the geckos. Two females of approximately the same size will usually do fine together as long as they have enough space (15 gallons should be fine for 2 adults). If the two geckos are of significantly different size though, the larger one may beat up the smaller, or out-compete it for food. Also, any new animals should be quarantined separate from any existing ones for a minimum of one month (but preferably longer) in order to ensure that they're not carrying any diseases that would make them both sick.
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0.1 Albino Leopard Gecko - Tigger
0.0.1 Crested Gecko - Pooh-Bear