If you are as much into reptiles and amphibians as I am, it is tempting to add other species to your crested gecko cage. I personally find this all the more tempting as crested geckos are nocturnal and therefore potentially leave the cage “unused” during the day.
Generally, most experts will advise against introducing any other species, unless your crested gecko cage is very large. The main reason for this is that other species would disturb your crested geckos and vice versa. In the wild it is actually very rare that different species’ paths cross and if indeed they do, there is ample space to avoid the other and hide. In a cage, obviously, space is very limited.
Another factor is that smaller lizards could also be regarded as prey for crested geckos.
So, rather than introducing other species to your crested geckos, you could consider adding more cresties. It should be noted, however, that male crested geckos tend to be aggressive towards other males. Depending on the size of your crested gecko cage, you can keep one male and two or even three females. Size and the number of hiding places are a crucial factor here though. We recommend a 15 gallon tank for two crested geckos and 20 gallon tanks for a group of three geckos.
Before introducing any new gecko to your cage, you should keep them in a separate quarantine tank for at least three months. You need to do this in order to keep communicable diseases and parasites from spreading to your existing gecko population. Keep the decoration of the quarantine tank to a minimum and use kitchen paper as substrate. This makes keeping everything clean and hygienic and you will be able to check that the excrement has a normal consistency. Watch your new crested geckos on a daily basis to evaluate their behaviour, appetite and the consistency of their excrement.