A sump reactor hub utilizes a zoned plenum system to organize supply, drain, and/or recirculation through one or multiple reactor vessels, purposed for filtration and/or augmentation of aquarium water. Each zone comprises sub-plenum partitions which direct the passage of water through all stages of a reactor system. Flow between each reactor and its sub-plenum zone is achieved through access points; gaskets; and connectors. Undesirable flow is contained by plug and/or valve assemblies. Each reactor may be completed by a dedicated outlet or drainage assembly connected through the same plenum system if not intrinsic to the reactor. The present invention allows for modular manipulation of any given aquarium filtration strategy. To this end a variety of reactor types are described to complete this modular filtration system. Such reactors are purposed to address all forms of chemical, biological, and mechanical filtration/augmentation of aquarium water.
