It's not hard to make your own reactor and its quite cheap. Furthermore they last forever. I reccomend this above diffusers. My sig has a link to making a in line filter reactor. It also works with pressurized or DIY.
First find some hose barbs that fit your powerhead or filter tubing and have NPT thread connections.
You need a piece of ~1 1/2' PVC
with a 1 1/2" diameter (smaller for smaller tanks)
Reducer bushings (end caps) to fit PVC
and hose barb NPT size
Couplers for Reducers
Hose Clamps that fit your barbs/tubing
Airline connectors for CO2
Bioballs or similar media
Teflon Tape/Pipe Thread Tape
I also used solid epoxy 'goop' but I can't say that really made a difference, the silicon works fine.
The design can be completely adjusted to fit your tank, running a small tank? Use smaller diameter PVC
and adjust the rest. Want to see your reactor at work? They make clear PVC
. Reactor getting clogged? take it apart and spray it with a hose through the reducer bushings (mine hasn't gotten clogged yet after 2 years.)
Its all about the seals. The hose barbs should have their threads wrapped in Teflon tape or yellow pipe tape. The airline connector should be sealed with silicone. The PVC
of course takes PVC
glue, which is perfectly safe once it is dry BTW (nobody told me that and I worried like crazy when I first installed it, doesn't help that it smells like turpentine). The hose clamps ensure the needle connectors stay sealed. After that the rest is common sense assembly.
This reactor works by taking water in the top, and CO2
in the side just below the top. The water hits the CO2
on the bioballs and smashes it into pieces. Whats left will be broken up by the filter or powerhead.