Using Horticultural Charcoal with Aroid plants
a few reviews from amazon customers:
'An essential cleansing item for my Aroid potting mix. As well as acting as a cleansing agent it is a stable edition, helping to aerate the soil, and therefore preventing root rot, the worst nightmare for Aroid growers. The delivery was well on time, the price is right and my dealings with the support team most enjoyable.'