Is Ground Walnut Shells okay?

[Nerien]

Hubby tried to get some sand for my crazy nesting finches today, but nobody within lunchtime distance of work had any. There is a pet store next door, he came home with a bag of "Ground English Walnut Shells," intended for use in reptile enclosures.

Is this safe to use in the bottom of the finch cage? They seem to be very good at sticking their little beaks between the wires of the bottom grate and getting to the stuff underneath, hence the need to remove the paper before they fill the entire large-size basket nest.

If not, he can return it and get corncob stuff, instead. That would be okay, right?

he also said they had a bag of ground coconut shell grit, again intended for reptile cages.

[debbie276]

I'd be careful with the corncob stuff, if it gets wet mold can follow quite quickly.
Walnut and/or coconut shells should work. Your just putting a thin layer over the tray to prevent the poop from sticking.