Both systems have pros and cons.
Plants do need elements to grow, there is no way around it. The difference is in the delivery systems.
ADA uses a substrate working as a “sponge”, taking elements from water column and storing them for the plant’s roots. This process cleans the water while supplies the plant’s needs. Unfortunately, this is difficult to control, it does require water changes and the substrates don’t last for ever.
EI uses rough amounts of most of the elements added to the water column and doesn’t rely on substrate in terms of some nutrients. A system that usually works with every substrate and is relatively easy to restore and modify. Unfortunately, it may create toxic concentrations and water changes are crucial. |