DIY Poor Mans simple Overflow Box (~$10)

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Aquarium Advice Apprentice
Nov 29, 2003
Waterloo, ON
On sunday I almost bought an expensive overflow off eBay but I lost the auction, then yesterday I got an idea to just use a simple gravel vaccum and a small jar to create an overflow box.. er overflow cylinder! I just wanted to try hooking up my aquarium to another small one, and i dont need a huge flow rate or a huge gygantic overflow box hanging over my aquarium. So here you go:


1 Gravel Vaccum with hose (cost ~$10)
1 Thin cup like thing (I used a spice jar)

All you do is put the jar down the cylinder, and feed the tube coming from the overflow inside your aquarium into the jar. The jar will preserve the cyphon, and water just flows over it and down the cylinder!
I added some plastic bits underneith to keep the jar from falling right to the bottom. It works quite well! Might be a good idea to seal the cylinder and the green cap with some silicon. If you need a tube to go from the overflow on the back to the one inside your aquarium you can just cut a small length off your gravel vaccum tube.

Also I drilled a hole at the top of the cylinder for a hook to hang on the aquarium.
Heres the picture

Heres my crappy overflow from inside the aquarium, made out of a spent bottle of Buckleys with holes drilled into it. I need to add some more holes and fasten it better with some proper dudads but I havent figured out best how to do this. I havent secured the tubes either so Im going to turn it off until i fasten them properly.

Anyway this was fun.
This is a very cool idea. Tell me more about it, will you? What's in the "other" tank? What is your return pump? Does the return pump drive the overflow into the cylinder, or is the hose syphoning into the cylinder?
My big tank is 33 gallons and the smaller tank is 5.5, and I keep a two spotted rasbora in there by itself because it was eating some smaller harlequins and tetras that were in my big tank, but I hardly take care of the small tank so I figured id try linking them together. Theres no small overflow boxes out there so its a good thing I made this one instead.

The return pump in the small tank is a Hydor Pico 300 and its driving the overflow into the cylinder as long as the cyphon doesnt break.
Lees speciman containers can be used for a cheap solution. I made one awhile back. I like my internal overflow better.

As long as it works and it safe...
Kramer said:
I need to add some more holes and fasten it better with some proper dudads...


You must know my girlfriend...


Nice looking overflow - I'm always a fan of simplicity and that certainly did it!
So does the height of the top edge of the spice jar determine the water level in the main tank?
^The overflow on the inside the aquarium determines the water level in the tank, as you can see where the holes are is at the water level of the tank.
The top of the spice jar has to be within the depth of the overflow thats inside the aquarium.

So with the cost of the overflow, pump and to secure everything properly:

overflow box: $10
pump: $20
silicon $7 (used only a tiny bit of it)
3 elbows $3
tube for return $3

Total: $43 cdn

Heres rest of the pics now that i fastened it.


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