Venturi Design

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fishface

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Re: Venturi Design

Tom Barr said:
I'd rethink your approach and rational behind stable pH with CO2 being better for fish.
Tom Barr

will do! that's why i joined here...to learn from the people with experience! i only started planted tanks 5 months ago and have to admit the learning curve has been pretty steep for me.

so...i will ditch the co2 after lights out! check! thanks for your help Tom :D

ps will this also make a difference in the health of my filter bacterial culture equalling cleaner water cause they'll get more 02?
 

chubasco

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Jan 24, 2005
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Re: Venturi Design

Shutting off the CO2 in a DIY yeast setup at night would be difficult, if not dangerous.

This would have to be for compressed gas injection only, right? I found
a good deal on a 5lb CO2 bottle (free) so now I'll probably go that route in
stead of DIY yeast, which got to be a bit of a hassle the last time I used
it.

Bill
 

Tom Barr

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Re: Venturi Design

Bill, that's why this reactor is cool, it was the only way to use a reactor and still throttle CO2 on/off using DIY CO2.

No CO2 is dssolved when the powerhead is turned off, so sinmply adding the powerhead to the light timer achieve the goal, of dosing CO2 only when the lights are off.

This way the CO2 DIY gas never stops flowing and safely burps out to the air above when the power head is stopped. Same deal with a powerhead used alone also, this just diffuses the flow downward and gently and maximizes the dissolving of the gas till lots of O2 is present.

You can use a solenoid set up with a DIY CO2 system though without blowing the cap off etc.

You use a Tee, the Tee branch that comes down, the verticle line in the "T" has the solenoid attached, the straight part of the T goes to.from the DIY CO2 and the reactor.

When the solenoid valve shuts ooff ansd closes, this pressurizes the line the gas goes into the reactor, when the solenoid is open and "on", the gas vents out to the air.

It's called reverse solenoid application.

I did this but powerheads cost 9-12$, solenoids at the time cost 40$.

To my knowledge, I am the only one that has ever done that with DIY CO2 + solenoid on plant tanks.

There's no need though since the powerhead controls the on/off part.

Regards,
Tom Barr
 

chubasco

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Jan 24, 2005
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Re: Venturi Design

It's called reverse solenoid application.

I did this but powerheads cost 9-12$, solenoids at the time cost 40$.

To my knowledge, I am the only one that has ever done that with DIY CO2 + solenoid on plant tanks.

There's no need though since the powerhead controls the on/off part.

Regards,
Tom Barr

That's good to know, and yes, that is way cool! Thanks, Tom!

Bill
 

Tom Barr

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Re: Venturi Design

bill ruyle said:
That's good to know, and yes, that is way cool! Thanks, Tom!

Bill


Once you understand what the tank needs, then the many ways of doing something are magically very similar and not so difficult to understand nor apply. Then you can decide which are best for your routines and methods.
I do suggest folks try things as they become comfortable and can re set things without too much anxiety.


Regards,
Tom Barr
 

chubasco

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Jan 24, 2005
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Re: Venturi Design

Tom Barr said:
I do suggest folks try things as they become comfortable and can re set things without too much anxiety.


I'm going to be making a couple of these as soon as the viewtainers arrive
for a couple of 10s and one 15. I've got some RIO 50 powerheads (cheap
at Bigalsonline) that I'll use. Reactor position in these shallow tanks: I was thinking of having them mounted about 2 inches off the substrate. Is this good, or not? Or does it matter....

Bill
 

Tom Barr

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Re: Venturi Design

bill ruyle said:
I'm going to be making a couple of these as soon as the viewtainers arrive
for a couple of 10s and one 15. I've got some RIO 50 powerheads (cheap
at Bigalsonline) that I'll use. Reactor position in these shallow tanks: I was thinking of having them mounted about 2 inches off the substrate. Is this good, or not? Or does it matter....

Bill
I generally place them higher since the water is going down already and then comes back up but it's no big deal.

Regards,
Tom Barr.
 
F

fishface

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Re: Venturi Design

bill ruyle said:
I'm going to be making a couple of these as soon as the viewtainers arrive

what are viewtainers and where do you get them from? :confused:
 

Milan

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Sep 28, 2005
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Re: Venturi Design

Tom, I'm trying to figure out the venturi loop used in your design. I think I understand the concept, but there is something that is not entirely clear from these images, so if you could be more descriptive, it would be appreciated.

Did the powerhead originally have a venturi input, or you just stuck an air hose in it's inlet? If improvised so, I'm afraid that would produce quite a bit of noise from the gas getting into the impeller chamber, not to mention reduced flow rate and shorter impeller life.
Thanks
 

Tom Barr

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Re: Venturi Design

There should be both a pic and a drawing to show what goes where.
It's not complicated and I think most folks over complicate it.

regards,
Tom Barr
 

Milan

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Re: Venturi Design

Don't take me wrong Tom, ... I'm not trying to bash the design, but to make something that is workable, and efficient for me. My question was if the power head you are using has (by manufacturer) a venturi input on it's inlet, or you imrovised it? I can clearly see from the diagram that the loop goes into the inlet. What's inside, I can't see because it's not shown. Normally, venturi goes on the outlet, for the reasons mentioned in my previous comment, and this is where my question comes from.
 

banderbe

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Re: Venturi Design

Tom don't you have some more detailed guide on building this venturi reactor? Is this still the design you recommend?

I moved my L. Pantanal over right by my limewood stone and the difference just overnight is pretty astonishing. I would like to get better bubble circulation throughout my tank..

Thanks..
 

VaughnH

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Re: Venturi Design

banderbe said:
Tom don't you have some more detailed guide on building this venturi reactor? Is this still the design you recommend?

I moved my L. Pantanal over right by my limewood stone and the difference just overnight is pretty astonishing. I would like to get better bubble circulation throughout my tank..

Thanks..
The best way to get good bubble circulation throughout the tank is to go to the CO2 mist method. For that you can use a powerhead and either use a limewood stone under its inlet so the CO2 bubbles go thru the powerhead rotor and get chopped into very small bubbles to be blasted where ever the powerhead is aimed, or you can just run the CO2 tube into the inlet of the powerhead and let the rotor do all of the microbubbleizing of the CO2, which is what I do. The latter is a bit noisy, but it works well.
 

Tom Barr

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Re: Venturi Design

FYI, if you feed the powerhead with a small airstone, there is no noise.
Tiny bubbles make less noise.
So wrap, tie, rubberband, glue etc a stone to the intake basket etc of a powerhead.


Regards,
Tom Barr
 

VaughnH

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Re: Venturi Design

I made one of these reactors, and am now running it in my 45 gallon tank. I get pearling in about 2-3 hours after the lights and CO2 come on, and the pearling is just about as intense as it was with CO2 mist. I'm using about 2 bubbles per second or less, where I was using at least 4 bubbles per second with CO2 mist on my 29 gallon tank. No bubble of CO2 builds up in the cylinder. I just get small bubbles of CO2 which swirl around until they disapear, meaning it is 100% efficient in dissolving the CO2. So far I haven't tried to measure how much CO2 is in the water, or any other water parameter, for that matter. But, I am still using EI dosing. The reactor is shown below:
PICT0027.jpg

PICT0028.jpg

PICT0029.jpg

BarrReact.jpg
 

Tom Barr

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Re: Venturi Design

Yep, now you got the design down.

Regards,
Tom Barr
 

VaughnH

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Re: Venturi Design

I increase the bubble rate from about 1-2 bbs to about 3-4 bbs, and now it spills little bubbles out the bottom, which quickly float to the top. They aren't micro bubbles, but more like 1/16 - 1/8" dia bubbles. I haven't seen any bubbles near the venturi pick up tube yet. Is the big bubble you show in your sketch a conceptual bubble only?
 

Tom Barr

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Re: Venturi Design

Yes, ideally you'll have mist form after 2-4 hours and then through the remainer of the day, but larger bubbles is bad, more pump flow and better Venturi will help.

Also, does the flow from the pump spiral down or is the output directedly directly downward?

I cannot see inside the tube, this is a very important design that was left out in the Plant Guild copy of my orginal tube.

Regards,
Tom Barr