DIY air driven Gravel/substrate vac

This is an old post I made on the The Planted Tank in 2008 but I still have this thing and it works awesome! I figured I would share it on here as well.


The other day I was coming up with my new method of water changes and I needed something to clean up the tanks since I was just pulling out water and replacing it and not gravel vacuuming. I went to Petco and picked up one of their battery powered gravel vacuums and it burned out in 20 minutes and I wasn't about to exchange it so I used to have an air powered one a few years ago and it worked well for me. I couldn't find one locally and the shipping was more than the vac so I figured I would just make my own.

So here's what I did, I took some:

1/2" PVC the lengths will depend on you tanks and you can make different lengths for deeper and shallower tanks. You want to make sure you have a long piece on the back end of it or you can end up shooting water out the back all over the place if your air is set up too high.

1/2" PVC "T" coupling

1/2" PVC 45* coupling

1/2"x1/2" coupling

1 piece of rigid airline

1 air control valve

2 or 3 zip ties

A toe section of knee highs or panty hose

A section of airline long enough to move around your tank(s)

An airpump the stronger the better

A drill to drill a hole for the rigid airline

Here is my version, the T coupling bottom has a short piece of PVC in it to connect the 45* coupling to it and hold the sock on.
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Here is the front of it. I bent the rigid airline by heating it with a lighter. Make sure you don't collapse the airline when bending it, go slow and let it cool a bit as you are bending it, use pliers if you have to so you don't burn yourself. I matched up my drill bit to be just a 1/64" smaller than the airline and I drilled at an angle so the air bubbles would follow up the PVC better not sure it's necessary or not. I cut the tip to be at an angle so I have a better view of what's going in it as I have mostly sand tanks.  

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Inside view

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Here is the back end I angled it so I could keep the airline out of the way while I was using it.

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For best results you would want to keep the T and 45* area where the sock is closer to the water surface.I find with sand it's best to work backwards dragging it on the surface of the sand, this stirs up the mulm and gets less sand in it because the mulm is lighter than the sand.


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So, the air bubbles create a current up where light debris are picked up by the bubbles and the soft current. Then the debris drop into the sock... Interesting. What I like is its size. I have a small tank where this would be very handy. Has lots of mulm/ fine debris. Its in a tank where its hard to get a big O suction tube into and get into the small corners.

Thanks for sharing!

Yeah this is a great DIY. Might have to make one of these for the shop some day.

Great DIY! Another great idea I can't wait to try out!

Thanks guys! Yes it works great and if you want to play a prank on someone walking by you just tilt the back of it level with the surface of the water for water rocket! lol My fiance didn't seem to think it was as funny as I did though...  

LOL!