Arowana Avenue - JBL Micromec would be a capable assistant in your filtration as it's able to biologically breakdown the pollutants in both fresh and saltwater aquariums. It creates intensive water clarification
JBL Micromec 1l, Sintered bio-Glass Balls for Aquarium Filters for Breaking Down pollutants : Amazon.ca: Pet Supplies
JBL NitratEX
Seachem Matrix Review: Vs Eheim Substrat Pro & JBL MicroMec | Organic molecules, Matrix, Aquarium