I recently bought a small aquarium air pump, not really realizing that “pump” in this case meant blowing air, not sucking. A quick search turned up almost no information online, but converting it into a vacuum pump turned out to be quite easy.
Why might you need a vacuum pump? I’m using it for picking up swarf while cutting vinyl records, but this would also be useful for getting rid of bubbles in mold-making or casting!
I’m using this pump which I got for $13 on Amazon. It’s very small and fairly quiet. To convert it to a vacuum pump, remove the four screws on the back. Inside is a small transformer and two arms. These arms have a magnet at each end, which is pulled by the transformer to activate their rubber bellows. Fortunately, to switch the pump, we just have to reverse the air inlet/outlets: suck air in, push air out vs suck air out, push air out.
Pry up the plastic bellows assembly with a small screwdriver, like shown above.
The inlet/outlet are above, sealed with a rubber O-ring. Pull the assembly out carefully and spin it 90º. Then just push it back into place. Be careful that the O-rings are seated properly, as they seem to want to pop out.
Close up the pump! You may need to seal it using caulk or hot glue if you’re not getting good suction, but mine seemed pretty good without.
Finally, attach the tubes. For more suction, the two tubes can be combined using a T-connector (my pump came with one).
Nothing earth-shattering, but hopefully this helps someone with a similar need!
27 Replies to “Reversing An Aquarium Air Pump”
Neat hack! Its hard to tell from the pictures but do you think it could be rigged to have one tube for suction and one tube for exhaust?
I don’t think so, but it would be easy to try. It doesn’t offer much air pressure, so doubling really does help.
Just bought one and will give it a try.
Do you need to rotate both sides?
Yes, I’m pretty sure you do. It doesn’t have a ton of suck, but is really quiet.
Cool. Did you tried with diamond and Shank blanks?
Could you suck all the swarf?
Got the 100 series. Is the same you got?
Also how did you connected the inline switch? How do you know what cable to connect? It doesn’t matter?
I haven’t used good cutters or blanks, I was cutting acetate with a cheap cutter, which doesn’t work great but is really cheap :) It sucks well with long, continuous swarf, but my tube got clogged very fast as the shavings compacted. Will have to do some more testing to see if this can be resolved. The pump I got was the Tetra 60, so the 100 will probably be even better.
Not sure what you mean? The power switch was left untouched. For the tube, I used a T-joint to connect to both outlets (which are now inlets).
Thank you so much for this! I bought the same pump with the impression that Id be able to access both the inlet and the outlet… nope…. Im off to try your tips!
Interesting, was wondering how to do that.
Thanks for the post.
Hello jeff. I bought same pump but with one hose outlet. The plastic that you pry open in my is almost seal. I could not get any screw driver in to pry it. I think it is glued in. Do did you do it
@Kenneth — yeah, you kind of have to pry it open. I used a really small flathead screwdriver or maybe drill a hole to get it started. Hopefully they haven’t changed the design too much!
Thanks for the response. When did you buy your pump. I just bought mine. Maybe there is a difference in design between the 100 that you have and the 40 that I have. May I send you a photo of mine.
I bought it in 2015. I’m traveling now but can take a closer look when I get home.
Sorry but am having some problem sending the photo. However I have a feeling that the plastic is sealed. I wonder of would damage something inside by cutting around it to get in.
Hello jeff. Do you know of any othersuction pump with the same size as the one have or one that can easily reverse to a sucking pump? Thanks for the assistance and your response.
@Kenneth – I think the insides are pretty sturdy. You could maybe try drilling a small hole in the seam then stick a screwdriver in there to pry it loose. I think once you get it started it should come apart pretty easily. For other pumps, I really don’t know. I got this one because it’s so quiet. I know people use airbrush compressors to create a vacuum for casting rubber and plastic, so that might be an option. Not sure where you’re located, but Harbor Freight sells them very cheap.
Hello jeff. I had some friends of came over to help .We tried to get in but but in the process damaged something inside. It was too difficult to cut through the plastic . So we just gave up. I
I needed the vacuume pump for an old japanese turntable I picked up while I was over there. It requires a suction pump to work. It is similar in size and specification to the one that you converted and the one that I have tried to convert, The turntable is totally useless without the suction pump. So if you ever find another one or no longer using your pump I will be most grateful if I could buy it from you. Thank you so much for all your assistance.
Interesting post. Is there anyway to access/channel/collect the air coming out? I need a pump similar to these that has an inlet and outlet port, but haven’t found one yet. Thanks,
@Brian – I took a look at the bottom and it appears there’s a filter and a big hole for the air to vent (or get pulled through in it’s original use). I suppose you could glue some kind of hose adapter on there but the air would be flowing through the body of the pump first.
What size tubing did you use I m just purchasing the same pump for use with my Scully instead of the heavy Henry hoover. Thanks again for sharing.
By only reversing only the one side, would it be possible to have one hose with negative pressure and the other positive? Would they exchange air within the pump?
@Byron, it’s been a long time so I’m not sure? I think I went to Home Depot or something and tested out what fit. The pump might also include that info in the instructions. Sorry!
@Christian, I don’t think that would work but I suppose you could try? I don’t remember why it has two inlets/outlets but given how cheap the pump is, I doubt that it would be possible.
What kind of pump is this and where did you get it?
@Christian. No, it will not work. There is a specific left and right side to the dual membrane air pumps. They have to be swapped in order to reverse the airflow, also note there is typically only one intake/exhaust hole and filter.
I’m currently researching and experimenting with a tetra air-3000 dual port myself. After swapping the membranes and joining both air “intake” lines I’m able to pull a vacuum down to 5.75 InHg. Surprised the heck outta me too! Lol. This would be more than adequate for vacuum filtration in a lab on a vacuum flask and Büchner funnel.
I’m currently trying to increase the vacuum with slight adjustments to the magnet bars. It may reduce overall life of the membranes but for the application I’m using them for its negligible
If anyone has any ideas on how to boost “airflow” or vacuum pressure please jump in. Specifically I’m interested in the magnent placement and membrane sizes without replacing to many parts or power supply… that being said I wonder if I change something on the motor to increase power….
Thanks for posting this! The rotation is 180 degrees, not 90 degrees.