Reef Aquarium Sumps

Reef aquarium sumps have many useful advantages for your aquarium.

What is a sump? Do I need one?

A sump is really just an extra water containment area. Most of the time you would place the sump under your aquarium, in the stand, but they could be placed almost anywhere. I have mine in the basement, in a special room I call my equipment room.

Water flows from the main tank to the sump, usually just by gravity. Then a return pump is used to pump the water back to the display tank.

Reef aquarium sumps can be as simple as a single chamber plastic (food grade) container. Some can be a very complicated custom made acrylic tank with several chambers.

Here are some of the many advantages of using a sump in your setup.

First, they will raise the overall water volume of your system which makes your aquarium more stable. More water means more room for error. If anything should start going wrong, you will have a little more time to correct it.

Second, they provide a place to put most of your equipment. Things like heaters, monitoring probes, skimmers, grounding probes, etc can be placed in the sump. This will give the display tank a much cleaner look.

They provide a perfect place for a refugium with macro algae, more live rock and live sand.

Reef aquarium sumps provide a consistent water level in the display tank. All aquariums are subject to water evaporation, some more than others. My 90 gallon reef tank loses about 3 gallons a day to evaporation. By having a sump, the evaporation shows up there and by utilizing an auto top off system the evaporated water is added when less than a quart is lost. The water level in the display tank never varies. Another advantage is the increased circulation provided by the return pump. You can point the return nozzle in almost any direction where it enters the display tank. This is like adding a power head for free in the tank.

A sump is a safe place to perform many maintenance tasks such as water changes, adding additives and testing your water parameters.

There are many successful reef aquariums that do not have a sump, but there are a lot more that do use sumps. Do you need one? No, but if you have room for a sump, you should consider it.