Sumps

A sump is simply an auxiliary tank placed below or beside your display aquarium that houses essential aquarium life-support and filtration equipment. Water flows from the display tank down into the sump through overflow plumbing. It then passes through sections for mechanical, chemical, and biological filtration (filter socks, media reactors, refugium, etc.). From there, it's pumped back to the display tank by the return pump.

Some sumps even have additional accessories like dosing line holders, probe holders, and heater holders to make your whole setup tidy and efficient. Moving these systems out of the display helps improve aesthetics and gives you more flexibility in equipment choice. Adding a sump also increases your system's total water volume which promotes stability of water parameters.