Charcoal Powder

[Dani33]

I was curious if this safe to use as a bottom layer for naturalistic vivaria. When making plant only terrariums, it is beneficail to use it to keep the soil sweet, (not rot). The three layer would be charcoal, sand for drainage and organic soil. I have been thinking about getting some kind of amphibian and making a show piece for my living room. Thanks in advance for your replies.