If you like the bark chips I suggest you check out cypress mulch from the garden centers. Holds moisture great as cypress is a spongy wood. It is also cheap!
Just make sure you are getting plain cypress and not the stuff that is dyed red.

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Merlin,
What's Life Without A Little Magic!

I don't think eco earth is that expensive, i buy it in the bricks in a 3 pack, with my store discount it comes to like $8-$9. That 3 pack makes alot of substrate.
But to each his own.
I use excavator clay for my skink, with a thin layer of dry eco earth over that, but everyone else gets eco earth. I'll be mixing up my own substrate for my tegu's cage though, i'm close to switching my Boa into a bigger tank, and the tegu into the tank its in now.

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"Nobody can do Everything, but Everybody can do Something."

holy crap.... my local store sells the bricks for 6 bucks each. what is excavator clay? never heard of it, but would it be useful for Leopard Geckos?

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0.0.1 - Jack, Ghost corn, never sexed, but its a He darnit
1.0.0 - Neo, Columbian Redtail Boa. Everybody's best buddy :) except my roommate.... he bites my roommate....

Excavator is like a clay sand mix. It comes in a loose sand like form, mixed with water it becomes more like clay, you can mould it, make caves, whatever. if used properly there should'nt be a risk of impaction, it dries solid, almost rock hard.
in my opinion It would defintily be better then sand for a leo, I have not had problems with it with my skink, but it can get expensive. usualy about $15-$17 for a ten pound bag, i think i used at least 4 bags for my 20 long.


Here's a link to what my skinks enclosure looks like with it.
Skink and His Enclosure

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"Nobody can do Everything, but Everybody can do Something."