How to Use a Sump for a Freshwater Aquarium

An aquarium sump is a water tank externally connected to the main tank via an intake and outtake set of water lines. The sump is generally out of sight, and houses the filtration equipment. A sump increases the amount of water in the tank, which increases the diffusion of elemental buildup of ammonia and nitrates, as well as creating a more stable pH balance. Due to the large concentration of nitrates in the sump, it can also make an ideal grow tank for underwater plant life. The sump tank normally holds half the capacity of the actual fish tank.

Things You'll Need

  • Sump pump aquarium kit (two-chamber tank, submersible aquarium pump, 2 x flexible tubing, PVC piping, exterior overflow skimmer)
  • Manufactured aquarium filter material (optional)
  • Natural aquarium filter material (optional)
Show More

Instructions

    • 1

      Determine how much power the pump will need. This is determined by how many gallons your tank is. The gallons per hour (gph) power rating of the pump should allow for the pump to circulate the entire tank's worth of water about 10 times in one hour. So for example, if you have a 10 gallon tank, you should look for a pump with a 100 gph rating.

    • 2

      Determine where the sump will be housed. Below the level of the fish tank is essential, to facilitate the suction process of the water exchange. If you have a tank with its own independent stand, then underneath would be a good location. Prep this area by moving any electrical appliances from the area.

    • 3

      Choose a type of filtering system. Natural filters are commonly a combination of carbon, porous rocks and sand. A manufactured filters frequently used in filtration are "bio balls." These break down the bacteria and waste. The last line of the filter process, for natural or manufactured is often a filter media, such as filter wool. This is designed to trap all of the microscopic particles.

    • 4

      Set up the sump tank. Wash everything thoroughly with a mild soap and a non-abrasive sponge, making certain to rinse all soup off. The sump tank should come divided into two chambers, with one of them possibly smaller than the other, designed for the filter. If the bottom of the chamber is slightly raised from the rest of the tank with small holes on the bottom, line the bottom with the filter wool. Fill the chamber with either the natural or manufactured filtration medium. The other side is where the filtered water will go. Place the pump here.

    • 5

      Prepare the fish tank for the sump pump. On the back of the tank, place the overflow, which will attach by submerging one side of it in your tank and the other side will hang off the back. A "U" shaped hose will lead from one side of the overflow to the other. The exterior section of the overflow should be attached to one of the flexible tubes. On the back of the tank slip the inflow on. This should hang over the edge in a similar fashion, with one end being submerged in the tank and the other end connected to the PVC piping that should have a flexible hose attached to the end and lead down to the sump tank.

    • 6

      Attach the sump tank to the fish tank. Attach the inflow hose on the fish tank to the pump in the sump tank. Secure the overflow hose into the filter material section of the sump tank.

    • 7

      Test out the sump pump for any leaks. Plug in the pump to see if there are any flaws.