Originally Posted by digger
You're using a gravel vac as an *external* reactor? As in outside the tank? I'd like to see pictures.
I did this the way I had it imagined, since there is not much to see, I will describe it for ya...
I used a 10" Gravel vac (by TopFin, whatever) with two endcaps, and connected it inline with the inlet side of the canister filter.
Why inlet side?? Two good reasons: 1) since the canister is below the tank, the waterflow goes down on the inlet side, and up on the outlet. Bubbles have a tendency to go up, so using the inlet side I don't have to loop the whole thing, it just goes straight in line with the hose. 2) The purpose of the reactor is to extend the exposure to water so the CO2 dissolves. If I put it on the outlet side, I am getting very little bubbles of CO2 coming out of the outlet, which I found somewhat distracting. Not sure what the fishes thought about the constant bubble bath. On the inlet side, 100% of it is dissolving.
The CO2 just bubbles into the inlet strainer.
There is nothing in the "reactor" that would clog or have to be cleaned. It simply provides an area of currents and slower flow so the bubbles get smaller and smaller until they get sucked into the filter, where they completely dissolve.
I am a little nervous about that gravel vac leaking, but so far so good, since the whole connection is rather straigth, there is no force bending or pulling it, so I think it should be okay. Maybe I will add a little silicone to it later to secure the caps even more.