Cheap, Easy DIY Aquarium Sumps

A new sump with three compartments including a protein skimmer

Gtstricky / Wikimedia Commons / CC BY 2.0

A sump is nothing more than a container in which to hold water and other stuff for your tank. Normally located under the tank, saltwater aquarium sumps can be used to hold a wide variety of pieces of equipment used in marine aquariums.

Sump Equipment

  • Protein Skimmers: Some skimmers are specifically designed to be operated in a sump.
  • Live Rock: Many aquarists place a quantity of live rock in their sumps to add a lot of surface area to their biological filter for increased ammonia processing. Relatively inexpensive, highly porous base rock works very well for this. Another a good place to "seed" live rock to be placed in another saltwater aquarium for fast cycling.
  • Wet/Dry Trickle Filters: Placed in the sump are out of sight while they do their jobs.
  • Beneficial Macro Algae: Aquacultured in sumps (add a simple light fixture on top of the sump) with a number of potential benefits including nitrate and phosphate reduction in the aquarium water as well as potential food for your tank critters.
  • Mangroves: Add a light under the tank and mangrove plants will grow very well removing unwanted nitrates, phosphates and other toxins from the tank water.
  • Mechanical Filters: The first filter when the tank water overflows into the sump.
  • Aquarium Heaters: Placed in the sump instead of hanging in the aquarium are out of sight and not subject to accidental damage.
  • Automatic Top off System: Float valves are easy to install in a sump. No more hauling top off water to your tank every few days.

DIY Options

Sumps don't need to be fancy, they just need to hold the equipment and whatever water is fed to it via an overflow from your tank. If you use your imagination, you will see potential sumps just about everywhere. Some examples are:

Plastic Garbage Cans

  • Available at most hardware and home improvement stores.
  • Usually cost less than $15.
  • Cut it down to fit under your tank.
  • Great for locating remotely (in the basement or in another room).

Plastic Storage Containers

  • Lots of sizes to choose from.
  • Usually cost less than $10.
  • Available in most home improvement stores.


  • Available in a number of sizes and shapes.
  • Garage and yard sales are good sources for used aquariums that can be purchased for very little money. Make sure to perform a wet test to check for leaks before installing.
  • An easy DIY project, DIY glass aquariums can be designed to fit under almost any aquarium for a surprisingly small amount of money in very little time.

Why pay a small fortune for a commercially produced aquarium sump when an everyday household product will work just as well?

Mini-Reef Tanks are particularly good candidates for DIY Sumps. A sump can dramatically increase the equipment you can utilize in your aquarium system as well as add water volume to your nano reef tank system.