Re: Aquatic Plants Digest V2 #111

>From: tmarch at primenet_com (Todd March)
>Date: Fri, 31 May 1996 22:59:40 -0700
>Subject: Canister filter as a CO2 reactor, or...?

>I am setting up my new planted tank, with a DYI CO2 (yeast method) system
>intially, and am wondering what the best way is to introduce the CO2 into
>the aquarium? I was planning on using my Eheim canister filter as a
>"reactor", but am unsure as how to plump this. I've thought about drilling
>a hole into the intake tube of the Eheim, then inserting and silicon
>sealing a piece of rigid airline tubing, to which I can connect the soft
>tubing from the CO2/Pepsi bottle... I have been told that this might upset
>the canister motor with "excess air"....?

I'm using a DIY CO2 pepsi bottle generator with a Magnum cannister filter. 
Rather than hard plumb the gas to the filter as you suggest the way I've done 
it is as follows:

I run a rigid piece of tubing along the side of the intake pipe (lashed to the 
intake pipe with small rubber o-rings). At the end of this rigid tubing I've 
connected a 1/2 inch piece of soft tubing and cut a little "V" notch on the 
side of the tubing facing the intake basket. This forces the bubble to be 
picked up by the intake as opposed to simply bubbling out of the tube and to 
the water surface.

What I like about doing it this way as opposed to hard plumbing it is that if 
I want to count the bubble rate, I simply turn the filter off and count the 
bubbles that float to the surface. Because the setup pulls the bubbles 
continuously it is breaking up the larger bubble that would exit the tube. I 
hope that you can follow this rather poorly written discription. ;-)

On occassion I've found some bit of debris like a plant leaf blocking the 
bubble's access to the intake tube. So I check the thing regularly to make 
sure it is picking up the bubbles.

Just as an aside, I'd like to tell you and others a bit more about the rest of 
my setup. I'm trying to run a plant tank with a reverse UGF. The magnum pumps 
water down the tube of my UGF. I've read alot here about the necessity of warm 
feet for the plants, flow through the substrate, etc. I thought that a reverse 
UGF would fulfill these requirements. So far so good. The tanks been running 
about 5 weeks now. Plant growth is pretty good as I'm forced to trim 
continuously. To maintain a bit more biological filtration and water movement, 
I've got an old AquaClear 610 filter hanging off the back set for minimal 
surface disturbance. Had some sort of flowering sword that dropped seeds all 
over the aquarium and now there are babies growing everywhere.

Cheers, Rene