So I'm making Boon's mix which calls for Horticultural Charcoal around 5%. Does activated carbon (used in aquariums) serve the same role? I know they are not the same exactly. I'm not 100% sure the role the charcoal plays but I believe it hosts beneficial bacteria that would be found in soil as well as retain water. As charcoal has more air pockets due to how its created I would assume it's better at these things but often things are not so simple.

I just know one process that create coal. Hence all would be similar activated charcoal, horticultural charcoal, barbecue charcoal etc. Just stay away from compressed coal dust.

I havent heard about the bacteria theory before. In cases I use charcoal it is for purification reason. Not in bonsai thou.

But I am not an expert:)

Hey...

What I know about charcoal is that it helps on holding nutrients, however the amount you put on soil is just a little bit of shards, nothing crazy... I don't know about activated ones, and I wouldn't try since charcoal is so easy to get, brake into shards and sieve... But there is an crazy amount of acacia farms around here, so...

This is really interesting. Thank you for sharing this here.