The Atami pot filter ensures that no substrate ends up in your irrigation system with the drainage of your excess nutrient solution. Without a pot filter, there is a possibility that the substrate will end up in the filter of the pump of your irrigation system, which will cause your pump to have to work harder to get the nutrient solution through the filter, and which will eventually cause your pump to fail. An additional advantage of the pot filter is that your plants will not lose any of the nutrition they need. The Atami pot filters are custom made for use in our Wilma systems.