CO2 via Powerhead

I appreciate your suggestions in regard to dissolving CO2..however, that
method is far too inefficient--still 80% of the CO2 escapes into the

I have, however, since last posting devised a new reactor which appears to be
highly efficient.

I used a 2" PVC pipe section and capped it at either end and drilled a hole
on each end for input from the powerhead and an outlet on the bottom.  I have
a screw-on attachment on the Powerhead, so I attached 3/4" clear tubing from
the powerhead to the reactor and when I decided even THAT did not result in
an efficient-enough reactor I thought back on the wise words someone
indicated were the factors influencing CO2 dissolving:

surface area

Well, the turbulence was fine--I just cut the fins on the imepeller on the
powerhead until I reached an adequately slow flow (but still quite fast--it
was a 200 gph powerhead...) connected a completely sealed system (with the
reactor).  That gave me maximum "turbulence" since I have the output flow
from the powerhead entering this "chamber" from the top--causing a maximum of
splashing and mixing.

Next, I thought about surface area--how could I hope to design a system which
guaranteed maximum exposure of CO2 to water or vice versa.

A sponge...it works for nitrifying bacteria...why not.

So, in my simple reactor I stuffed a big sponge to prevent CO2 bubbles from
being blown right out of the chamber.

It works!

I've got my CO2 level up to 35ppm and a bubble once every 7 seconds.


Thanks for all your help.  I hope this encourages others to be creative about
their systems design.  It's of course not an ultimately controlable
system--pH fluctuates from night to day, but all fixed CO2 generators without
controllers have this failing.

And instead of buying a commercial reactor for mucho madeira $$$, I built it
for $8.50--somewhat less expensively than the $129 oxygen reactor that That
Fish Place tried to sell me.

Well, carry on.

Party on.

No...Swim on.