How to Build a DIY Saltwater Sump Tank

In this guide, I’ll be showing the steps to building a DIY sump tank for your saltwater aquarium.

So I recently purchased a 65 gallon fish tank to start my venture into the world of saltwater reefs. After much reading and advice from the local fish stores, I started to get the gist of the things I needed to do. I picked up a used setup for a great price off Craigslist and after much research I decided that a sump tank was going to be the next thing on my to-do list. I just went ahead and got a 20 gallon tank and some pieces of glass cut at the local glass/window shop.

Making your Saltwater Aquarium Sump Tank with Refugium

I had cut a total of 4 pieces of glass. One was 11″ tall, 8″ tall, and two 4″ tall pieces.  I ordered a protein skimmer but I didn’t have it at the time to figure out exactly how it would be placed so I just looked at the footprint size according to the manufacturer and gave it an extra 1.5″. Turned out that it was pretty tight, but it still fit.

After getting the spaces measured out, I made a section for my refugium (picture above, on the left), skimmer and UV sterilizer (in center), and return pump (right). The glass for the refugium is a bit tall but I made it that way so that the snails I plan on putting inside do not go to the skimmer side as I plan on putting a piece of acrylic over the refugium section and enough of a gap to just let the water spill down. You want to put the other 3 pieces in such a way (with 1″ spacing) so that the micro-bubbles from the skimmer do not get to the pump and eventually into your tank. Using liberal amounts of aquarium silicone, all the pieces were put together. I used CD cases to line things up and ensure straightness of the glass pieces while building the sump tank.

Finished & Tested Saltwater Aquarium Sump Tank

After 24hrs, fill it with water one section at a time to check for leaks and re-seal if needed and then you can add it to your system!

Don’t mind the wiring mess…everything to be cleaned up and refined soon! 🙂