When it comes to geckos, its best to keep them separate. There are many reasons for keeping them alone. Especially different species.
1. There will be be fights for hides, food, etc.
2. There is a hightened chance for the spread of disease.
3. There is also the stress that an animal endures when he feels insecure because of anotehr tankmate.
Keeping two geckos of similar size of the SAME species, both females can work, but not always, works i would say 50% of thet time
Keeping two geckos of a DIFERRENT species, both females, does not work 75% of the time.
I temporarily had to mix my one pictus with the leopard geckos, because my geckos are in a rack system and they dont have lids, and i thought, that the cornsnake might slip in there and eat them (cornsnake had gotten out, iguanas knocked cage over). So i put them all in the same tank with a lid until i found the cornsnake (which hasnt happened in 7 days). ANd by the next day (Both my leos who are around 8-9 inches each) both had severe bite marks all over their heads, body and tails. The tankmate, the pictus gecko, had been biting whoever has entered the hide that it was occupying.
Anyways, if you want to see pics i will show you, but its sad to see the injuries that they have had from a negligent mistake Ive done.
Please dont mix species for the sake of the animals.
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1.1 Green Iguanas
1.0 Bearded Dragon
0.2 Leopard Geckos
1.0.2 Pictus Geckos
1.0 Flying Geckos
1.0 Emperor Scorpion (R.i.P)
1.0 Brazilian Rainbow Boa
0.1 Costa Rica Zebra Tarantula
1.0 Cornsnake
0.1 Ball Python
0.0.1 Cuban Treefrog
0.0.1 White Dumpys Treefrog
0.0.1 Pacman Frog
0.1 Cobalt Blue Tarantula
(thats it for now)