Things You'll Need
- Acrylic or glass tank (approx. 20 gallons)
- Sheet of acrylic or glass
- PVC pipe
- Hand saw fitted with a plastic or aluminumum cutting blade
- Aquarium silicone
- Acrylic drill
- 2 submersible pumps (100 gallons per hour flow rate)
- Flexible plastic tubing (compatible with pump outlets)
- 2 PVC 90 degree elbow joints (compatible with plastic tubing)
- sucker and bracket pair (compatible with diameter of plastic tubing)
Instructions
Measure four sections of acrylic that are the width of your sump tank (minus the double the width of the glass) and 3 inches shorter than the height. For example, in a 36 inch by 18 inch by 18 inch tank with 1/8 inch glass, measure sheets that are 17 3/4 inches by 15 inches.
Clamp the acrylic and cut the sections with the acrylic saw. Ensure the acrylic does not flex as you cut. Sand the edges of the sections.
Measure a section to the left of the sump that will comfortably house the submersible pump and mark with the marker pen. Divide the remaining length of the sump into three equal sections and mark the divides between the sections.
Fit and silicone the first acrylic section to the first marked point on the tank (the pump section), ensuring it is straight and that the top edge is 1 inch from the top of the tank and the bottom edge is 2 inches from the bottom of the tank.
Fit and silicone the second acrylic section to the second marked point on the tank, ensuring it is straight and that the top edge is three inches from the top of the tank and the bottom edge is flush with the bottom of the tank..
Fit and silicone the third acrylic section to the third marked point on the tank, ensuring it is straight and that the top edge is one inch from the top of the tank and the bottom edge is two inches from the bottom of the tank.
Cut the course sponge into sections that will layer snuggly into the far right hand section of the tank. Fit as many layers as possible until the top layer is 1 inch from the top of the tank.
Cut the fine sponge in the same manner as the course sponge and fit it into the second section from the right, ensuring the top layer of sponge is flush with the top of the lowest divider.
Fill the mesh sack with the biological media and place it in the third section along.
Place your sump in the desired place under the main aquarium.
Fit one pump into the far left section of your sump and attach the flexible tubing to the outflow. Run the pipe from the sump to the top of your main tank. Cut off the excess pipe.
Join two of the PVC elbow joints to create a U shape and silicone together. Attach it to the free end of the plastic tubing and silicone in place. Hook the U-bend over the left side of the tank. Add additional pipe as necessary to reach 4 inches below the water line in the main tank.
Attach a second line of pipe to the second pump and place it in the far right of your main tank. Run the pipe from the submersed pump to the top of the tank and cut off any excess.
Join the second two PVC elbow joints to create a U shape and silicone them together. Hook it over the right side of the tank. Attach the plastic tubing from the pump submerged in the main tank and silicone it in place.
Run a final length of tubing from the far right PVC U-bend to the top of the far right section of the sump, allowing for the tubing to dip 1 inch into the tank and cut off any excess. Fit a bracket on the loose end and sucker it to the side of the sump. This allows water to drop from the tube onto the coarse sponge without the tubing moving around.
Allow the silicone to dry, which could take up to 48 hours. Always follow the instructions on the silicone packaging.
Fill the sump with fresh, conditioned tap water or water from the tank. For a saltwater tank, ensure the sump is filled with salt water of the same specific gravity and salinity as the main tank. Fill until the water is 1 inch below the rim of the sump.
Plug both pumps in and turn them on. Check that the water is flowing at the correct rate. Monitor the sump and main tank for several hours to ensure that the water levels in both are remaining constant. The water should drop onto the coarse sponge, flow through the sponge to the gap in the divider, be pulled up through the fine sponge and over the next divider onto the biological media and flow from there into the pump section where it is pumped back into the main tank. If adjustments to the design or build are necessary, turn off the pumps and empty the sump in order to work.