Venturi Design

[BHornsey]

Hi Underwurlde, I'm in Doncaster.

I got mine from Swell UK Underworld Aquatic Systems Maxi Jet Powerheads 400 - 1200 but I'm sure most places do them. I like the Underworld Aquatic pumps.
The tube was an old gravel vac that I got from Pets @ Home and I used a wooden air block on the CO2 delivery tube

Brian

[CodFather]

Hello just subscribed to the site. Love the layout and fuctions of the site/forum. Thanks for all of your hard work. I am interesting in the External DIY reactor but the link is sending me to a screen stating that a new version of hte site has been opened and that the team is looking forward to seeing me there. Maybe it's just my pc? Anyone having any success with the following link?

http://www.barrreport.com/gallery/browseimages.php?c=11

Sorry my first post is about the link. I'll properly introduce myself soon.

CodFather

[Tom Barr]

It does it when I clicked on the link as well.
There are several places that have a DIY external, notably Rex Grigg's site.

I'm without a camera dn time pinched at the moment, I will some day get around to DIY pic projects and post the gnarly versions I've designed for several applications.

Does not help you today though

Regards,
Tom Barr

[ccLansman]

Sorry to dig up and old post but i just really wanted to say thanks Tom for this amazing DIY. I just got mine up and running and for the first time ever have plants that are pearling like crazy. I did a few modifications but the design is almost exactly like you had it.

Thanks!

-Chris

Here is the venturi in action:
ImageShack - Hosting :: 1004194gb6.jpg

"the cool drag effect is due to the slowness of my cheap camera "'

[Tom Barr]

Thanks for the movie thar

The difference can be amazing when you tweak the CO2 CORRECTLY.

Everyone thinks I'm nuts about CO2, but you see the largest most dramatic differences when you add this fertilizer.

And once you see spectacular pearling and growth, you should sit down and remember it.

Then remember it again.
Just keep that one parameter in mind when anything goes sour.

Tweak that before trying anything to do with NPK.

NPK, Ca, Mg, Traces can be easily reset and tweaked(Large water change+ dosing them to non limiting levels asap afterwards). You KNOW those are in good shape after doing that.

The light is the same.

So that only leaves one variable in question: CO2.

The intense pearling and growth, without harming any fish, is the "test" that you have good CO2 once you rule out the nutrients/traces/lighting.

Thing is, measuring CO2 via the pH/KH has trade offs, same deal with the Drop checker, and bubble rates are not any better.

The best measure is really the plant growth rates/O2 production.
It's indirect, but it does measure precisely what we want to grow.

CO2 is funny, it can change dramatically in a few minutes, same with flow rates, and other parameters that are important to CO2/O2.

Regards,
Tom Barr