Glazed pottery tank safe?

Yeah the glazed pottery is pretty inert after being fired, go for it.
 
yes, but make sure it has no sharp edges and is not cracked.
 
wat if all of it aint fired???

Don't use anything that isn't fired. It will dissolve in your tank. You have to keep in mind that ceramic is essentially mud. It also tends to have some chemicals you wouldn't want in your tank (nothing you have to worry about once it's fired).

Even when it's fired, I'd be careful to only use food-safe pottery. Especially avoid cheap ceramics with bright red glaze, since a majority of red glazes have lead in them.

I use some pottery in my tanks, but it's stuff I made myself so I know what kind of glaze it has.
 
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