HOW TO: Build an AQUARIUM overflow weir – GOLDFISH aquarium


Building an aquarium overflow weir for your sump filtration can be done in many way using different materials. Here is how I built one for my goldfish aquarium.

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PVC overflow:
Modified PVC overflow with weir:
Weir using a bucket:
Bottom drain overflow:

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  1. Hey Joey, i know you are crazy busy right now with your gallery but i am about to set up my 40 gallon tank again but this time with a sump. i am worried about noise in its location. my plan was to use 90 degree elbows to the bulk head and put a sponge in them to keep my shrimp as well as the other fish from going through. i seem to recall a video where you made a silent overflow but am struggling to find it. do you have any recommendations for me?

  2. Just to confirm you said we can use silicone to hold acrylic together as long as it isn't under lots of pressure does that mean if I don't have Weld On I can use silicone to hold the bottom part of the Over Flow to the upper part?

    P.S. just built my first large glass aquarium 150Gal (7'L × 18"W × 24"T × 3/8" Glass) thanks to your videos and the Over Flow I'm building is for my 40 Breeder Sump that I will be using on it over all water volume Approx 180 Gal. Thanks for all you do Joey

  3. I have a quick question I have a 55 gallon aquarium I want to build an integrated filter for it but I'm not understanding the math to make sure I get enough turn over to keep it clean can you please help

  4. So does it matter where your drilled holes are in comparison to the weir? Located at the top fo the weir, bottom? Middle? I see a lot with more than one hole, can you get away with one? What is the reason behind that?

  5. Very usefull video Joey, thanx. I still have one thougt… when buliding a tank woth overflow… im about to copey your construction. Can I in any way build it so that you/I get a substrate cleaning effect, like when i use a chanister filter that circles the water down to the water inlet? It seems with overflow that alot of waist will sink down to the bottom of the tank and stay there.

  6. Hello i have a 130x34x34 aquarium with 4 – 2" drains i was told each 2" drain can handle 2200 gallons an hr is that right? i will have 3 internal overflows so if my slits are a 1/2 each would i need a total of 176 slits? To push 8800 gallons an hr???

  7. Hi Joe, Great idea. Now I am planning to update my fish tank. Right now I am using 2 gallon betta fish tank, so I am using only air pump in it. Now I am gonna buy 30 gallon flower horn fish tank. My doubt is should I keep both filter and air pump for my new fish tank? One of my friend said that keeping filter itself will circulate the air in fish tank. So please advise me what should I do?

  8. Hey Joey! What are some other fish that make good independent centerpieces in tanks? Sort of how your Arowana is great, and looks great, and also fills out a tank of its size comfortably.



Underwater Aquariums in 360° – Goldfish and arowana tanks!!

I made a BIG mistake!