How important is a sump?
The sump is the center of all complete saltwater filter systems. Using a filter pad or a filter sock can trap waste from the water as it enters the sump from the overflow above. We recommend purchasing the largest sump that will fit in your aquarium stand. Having extra space in your sump makes it easier to maintain your aquarium. Filter systems using in-sump protein skimmers and/ or submersible pumps require larger sumps than systems with in-line (external) pumps and hang-on or in-line protein skimmers. If you have room, you may place pieces of live rock in the sump to act as additional biological filtration.
