DIY venturi, a few easy builds for aquaponics, aquaculture or hydroponics..
This Video is from the Youtube channel: “Rob Bob’s Aquaponics & Backyard Farm”.
I really like the idea of aerating the fish tank by venturi to save some coin & help make the system quieter.. A mate shared an idea with me for a unit he had been working on & was happy with.. I decided to have a crack at his idea along with a few others to see which I thought would work the best for our set up.. I was most pleased with the results & ended up going with the "Bear Unit".. I have had one in the aquaponic fish tank for over 2 weeks now with no issues & have plans to add another to a moving bed bio filter that will be added to the system soon..
Was also very pleased with the off the shelf unit. That one will be going into the moving bed bio filter in the recirculating aquaculture system & is also being used in the fish tanks on the new aquaponics system.
This HAS been helpful Rob! I’m needing to put one in my fish pond and/or I may even build it into an vertical grow system (connected to the Koi pond) as well….I’m curious, what brand and model of pump you were using? Awesome video brotha, well done. ~Wayne
Wow, i’ve never thought about that! it’s an amazing way to provide oxygen.
i’m planning to do an aquaponics system as soon as i can. i find your videos very useful.
thanks a lot!
Great stuff Rob. Plan to do some testing down the road myself. I want to try to use a natural venturi to stimulate aeration in a deep water culture system. Also I’d like to see if I could gravity feed it, from a raised bed above.
Put a spray bar at the surface making bubbles and that will give you plenty of oxygenation . That’s how I set my aquaponic system up. Works great for me. So far everything we have put in there is growing good. Thanks for all the good info you share with us.
Charlie…
Hi Rob, from what I’ve read the size of the bubbles really makes on difference as their not in the water long enough to make a difference. It’s the bubbles breaking the surface tension that does the oxygenation but like most things their are as many schools of thought as ways to do things. Thanks for the video mate.
It’s one of those things that works but most everyone is wrong about why it works. A powerhead in the tank may be a better option than injecting dirty air into your water at high speeds
I’m sticking with the lots of little bubbles having a lot more surface area school Jack 😉 The bonus is that lots of small bubbles need to break at the surface in many places so no matter which way the O2 gets into the water both are covered with a decent running unit that pumps out a large volume of small bubbles..
Hope that makes sense… I need coffee I think :/
Cheers mate & have a great one..
Rob..
Have thought about using some shade cloth as the holes are smaller but I think we are both on the same page 😉
Shall be gluing up the final unit for the system this week along with 2 for the RAS as I think it has proven it’s worth..
Cheers Ra & have a great one..
to make the bubbles smaller have you thought of running a few layers of plastic window screening around the holes with a bit of distance between the layers to break up the bubbles? or you could use a wrapping of open cell foam to do the same thing. Open cell foam might trap and debris in the fluid though and require cleaning.
Hi there Thomas..Have had a few people suggest that thanks.. The bubbles we’re getting from the bar arrangement at the end of the delivery pipe are fairly fine where the ones in the tester barrel were just running from the end of the pipe so were rather large..
Cheers & hope you enjoying the holiday season..
Rob.
I used the 90 version style, but with a T (end with the pen pointed up and capped with a hole drilled in it) and used the bic pen. However I slightly crimped the end into a small slit. This dramatically reduced my bubble size and has been working well in my 450 gallon system for almost 3 months.
Nice one Don.. That was the only style I saw around when I first started to look into venturis.. Made one along those line but used the thin aquarium air line instead of the pen in the top of the cap & had no real luck with it so gave away playing with them for a while.. Would really like to play around with a dissolved O2 meter to see how well they really work when it comes to bubble size.. Have added it to my B’Day wish list with the boss but don’t like my chances 😀
Cheers sir & have a great one,
Rob.
The key I found to small bubbles was a 40% ish angle and then heating it and squishing it into a slit as well as adding a sponge to the intake. I had over purchased on my pump and had plenty extra so I took a T off the main outlet and diverted it back with the Venturi . I’m interested to see your next test.
Cheers for that Don.. Might be a while before the next test but will be playing around with them when I make up the bio filter for the AP later today.. Not sure if I will do a clip on it though.. Cheers mate…
I used similar constructions in fish tanks. If u get larger bubbles, it helps to run the outlet of the pipe against the wall of the tank. If you have some decent pressure then the large bubbles will hit the wall of the tanks and burst in small bubbles.
Worked really well in my fish tanks!
Hi there & thanks for that..
Ended up running with a few I was given in the aquaculture build but think the home made jobbies will get a run somewhere in the new system soon..
Cheers,
Rob..
If you dump the air en-trained stream into an inverted bucket the air would collect in the top of the bucket and be pressurized by the depth. a line to an air stone curtain bar would create the very fine bubbles you are desiring. Good luck. You may have enough volume for several air stones. The air get used twice to dissolve oxygen into the water. First as it is pushed into the Venturi by atmospheric pressure and again by the larger surface area contact in the smaller bubbles. Your going to get 8 ppm of O2 at 68 degrees F more as the temp of the water decreases. Heat increases the speed of the molecules and they break through the surface easier. That is why Pop goes flat as it gets warm. Heat drives any gas out of solution. aka the unknown chemist.
But you can dissolve more air into colder water!
Great info, thanks for making this video. I needed a quick and cheap solution to start adding air to my pond, as it’s been hot and dry here in Florida, at least for this time of the year. Coupled with it being too still, it was starting to stagnate and I didn’t want to end up with a fish kill if I waited too long. The pond’s main purpose is as a sort of fire hydrant, since there is no municipal water services where we are, but we enjoy the snakes, fish, frogs, and turtles that call it home as well. The ideas in the video helped get the job done, for now.
I’ve got an artesian well that’s used for keeping the pond filled, so I just added a venturi in to the line. I experimented with putting it at the start, middle, and end of the line, and having it by the valve works well while avoiding the problems with locating it elsewhere. (Debris, pond height, etc.) I did find that by extending the length of the air line coming in, it actually suppressed the sucking sound quite a bit. That extra length also allowed me to orient the opening towards the ground, protecting it from being bumped and keeping the opening from having stuff fall or blow in to it.
It’s not the ideal solution for my application, but I think it will help out until I can bury electric service out to it and buy a proper aerator for a pond this size. Again, your video was very helpful, thanks for taking the time to make it.
Simple Venturi For Pond Aeration
Nice one mate.. Thanks for the clip.. Looks like you’re getting a load of air into the water & am glad it’s worked out for you.. Are those solar pumps any good for aeration purposes ?
Cheers & all the best..
I really like your videos. They are the right mix of technical and conversational, and have kept me up many a nights figuring out how I want to expand my little backyard system! Thanks so much!
Thank you for this video and all the others. I just started building my system and watching your videos saves me a lot of mistakes. Hopefully my system will start and be better thanks to you.
Hey Rob! I came across your videos recently and have been enjoying them very much. You’ve done a good describing the function and construction of all the different components of an aquaponic system. I had an fairly simple idea that may help you decrease your bubble size and increase the oxygen saturation on your venturi system. If you were to add an aeration screen, like the one on a kitchen faucet, on the end of the PVC pipe, it should diffuse the the larger bubbles in the pre-oxygenated water, increasing the oxygen saturation without restricting the rate of flow much, if at all. Just a thought!
Mark Stephens – Houston, Texas
Hi Mark & thanks mate. One concern I’d have with that is the screen may end up getting clogged with solids. Can see where it would help out in some situations where the solids were all removed.
Cheers & all the best Mark.
Nice simple options, thanks.If a really efficient Venturi is required it does need a taper inside the water feed tube that has two angles. The air intake enters at the low pressure point.
Hi Rob. Subscribed already. That water fall into the sump tanks can be made into a super aerator by placing them into a pipe twice its size with a few slots resting on the bottom. The water pressure and splashing pushes the air down to the bottom of the tank through those slots. Peace
Have seen folks use something similar in their systems. 👍
Cheers mate.
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