01-20-2005, 10:58 AM
Join Date: Oct 2004
I have a 20 gallon high setup that may be similar to your preference. I use compressed CO2, which is fed into an external reactor that is plumbed into the outflow of a Fluval 204. The return from the reactor feeds a submersed spray bar, which is throttled down by a ball valve. I find that that the 204 provides a nice amount of flow for this size tank. On a side note, when I plumbed in the reactor, I replaced both the input and output hoses with smooth-walled tubing. I didn't much care for the tubing that came with the filter.
FYI, prior to switching to compressed gas, I fed DIY CO2 into the intake of the same cannister filter with success. It was, however, noisy at times, and it was not 100% efficient (i.e. every once in a while I would hear a whoosh, and CO2 would be expelled into the tank in the form of many not-so-fine bubbles.