from what i read, leopard gecko are nocturnal, does that mean that they are nowhere to be seen during the day ?
They are nocturnal, but you'll see them during the day sometimes, some will even sleep outside of thier hides if they're very comfortable with thier surroundings.
Also, i'm planning my terrarium with some nice hiding place, and some log to climb...do they like to climb ?
They need lots of good hiding places, including a humid hide to aid in shedding. Many do like to climb.
Finally, for substrate, coconut fiber ? Thats a very soft substrate that can keep humidity to a nice level.
Coconut fiber is not an ideal substrate for leos...it is difficult to clean, holds moisture, and can be eaten. Leopard geckos should not have sustained high humidity as it can cause health problems. They are from desert regions and like dry enclosures (with the exception of the humid hide and a dish of water). As far as a good substrate, my favorite is tile. It's very easy to clean, holds heat well, and if you get vinyl it can be cut very easily to fit your tank. It's also attractive and fairly natural looking compared to their natural habitat (if you get the right colored tiles...lol).
I'd recommend looking up some caresheets so you can get more information.
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Christina

2.3 leos
-0.1 tangerine het rainwater albino w/jungle background (Blinkers)

-0.2 jungles (Vahz & Skissor)


-1.0 tremper albino (Spitfire)

-1.0 tangerine rainwater albino (Bronx)
