HOW TO: Build an aquarium overflow weir

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In todays video we focus on how to build an aquarium overflow weir so you can ad sump filtration to your aquarium.

Videos mentioned:

DIY bulkhead fittings:
Drill an aquarium:
Plumb a glass aquarium:
Build a PVC overflow:
Build an upgraded overflow:
Build a submerged sump:
Build an emerged sump:
Build a fluidized sump:


The king of DIY


What do you think?


Written by The king of DIY

Content AuthorYears Of Membership


  1. All your videos show a bottom drilled tank with a stand pipe. Is there a specific advantage of a bottom drilled tank? Why not just drill at the back at the required height?

  2. I just see it as more work than required and a permanently modified tank. Plus takes up room in the tank. I made a diy 12 gal sump from a cooler and some spare odds and ends for my 55 gal. . Instead on drilling for the tank output or using a pump for the tank output to the sump. I used large hose black garden hose for both input and output to the sump. Then clear hose from behind the tank down into the tank. The output from the tank to sump has a 16 oz clear water bottle screen with filter around it so fish are safe and can’t be sucked in. From tank to sump is siphon powered and is made to where if the power goes out the water level in the tank can’t drop more than a couple inches nothing can overflow . And from the sump to the tank is a pump I modded to accept the garden hose The end result is simple easy to make takes up very little room and Doesn’t require any sort of modifications to the tank. And it’s whisper quite.

  3. Hey joey. This is an old video. I just started watching your channel. Really cool! Now you are a super star. 🙂 But, Can you cover the Wier with a two part black epoxy? Is is safe for fish?

  4. Just wanted to say thank u for your cost saving & simple alternatives to paying retail for essentials or upgraded options. Its a great benefit to lots of folks that probably never think to say thank you

  5. All that depends on the flow capability down to the sump being quite a bit greater than the flow up from the sump pumps. When the flow down is getting marginal – you'll first lose all skimming.. the weir water level will equal the tank water level.. because the increased head pressure in the tank forces the pump flow rate down the overflow/standpipe. For a 1.25" schedule 40 durso style overflow – that is about 600 GPH. 625 max

  6. Hey Joey, What you are doing for the community is great. My question on this build is that, after the weir is added to the build, do we still need the stand pipe? I am simply not able to understand the use of stand pipe once weir came on.

  7. How effective would the sump design be in filtering bottom of aquarium if the water at top of tank is the only thing that would enter the sump? Is this where power heads come into play to get the bottom water circulating?



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