Activated Charcoal: Is it absolutely necessary?
I have a 20 gallon aquarium to use for an indoor terrarium. This will be open at the top. I would like to use pea gravel at the bottom and a Metro Mix/Perlite mix.
Is activated charcoal an absolute must? I have a bag of cat litter (unused - just sayin') that contains charcoal. Can I use the cat litter instead of buying activated charcoal?
Any other ideas? Any feedback on my intended growing medium? I live and die by Metro Mix for all of my container plants, but maybe it is not right for a terrarium?