Ivan Harrison developed Aussie Gold Growing Mediums after realizing the normal mixes based on nitrogen robbing barks with volcanic pumic were not optimal for his orchids. These mixes held very little moisture and had no nutritional value. There are so many plants that need to have a mix that is well draining, retains some moisture, but not enough to contribute to root rot. They need a medium that allows for good air exchange, helps provide trace minerals, steril, to prevent plant infections from harmful bacterias, fungi, virus, and PH adjustable depending on what your plants or trees prefer.
Ivan hit the proverbial homerun. His patented mix, based on freshwater source Diatomite Rocks, ground coir and several other components, does everything better.