Simple and Cheap, this tutorial will assist you in making a CO2 reactor that will disolve your CO2 from a bottle (Purchased or Sugar/Yeast Mix) into your aqauriums water. I have found this reactor to work best in most planted tank setups and I usally get a 100% conversion rate at 3-4 bubbles a second.

Start
Materials:

Mini Gravel Vac
Small pump 200 Litres per minute +
Small rigid garden tubing 4mm
1 x Elbow Bend - Airline Type
Small length of Airline tubing
1/2Inch Heat Shrink
Heat gun or Butain powered soldering iron with heating attachment.


Disassemble Gravel Vac


Use tube cutter, hack saw or band saw to cut to appropriate length, no shorter than 5 inches.




The Gravel Vac I am using has a small valve for the "auto Syphon" to work, if yours has one drill it out with an appropriate sized drill bit. Once drilled, glue top piece back onto the vacuum with some "Aquarium Safe"
silicon or any other "quarium safe" Glue you may have lying around.


Now Take your elbow and rigid tubing. Drill a hole in the side of the gravel vac for the elbow to fit snug. Make sure to drill the hole at least an inch or two from the bottom of the Vac.


Attach Rigid tubing and elbow fitting, then insert elbow fitting into gravel vac.


Use a cable tie to secure tubing to the gravel vac.
That's Part 1 done.

In order for the CO2 to be diffused into the water, constant aggitation needs to occur. For this I'm using a small internal power filter to pump water from the tank into the top of the reactor so as the bubbles enter they are churned up and diffused quickly.


Materials
Small pump (this one is rated at 320litres per minute).
Heat Shrink.
Heat gun.
Pump attachments.

Depending on what pump you get, you should be given a number of attachments to go with it. Be sure that the pump you buy does have some sort of attachment so you may attach your tubing to it.

Heat the tubing that was provided with your pump long enough to become more plyable.


Slide tubing over your pump attachment.



Cut some heatshrink about an inch long and cover the connection. This will make the joint stronger. You may want to use some silicon aswell/insted of.
Completely up to you.


Once tubing is attached securely cut the tubing to an appropriate length and slide the open end on the new
reactor.


Place into a planted aquarium with the reactor upright. You may want to cover the open bottom with either pantyhose or filter media. I cut a sponge filter to size and plugged it in the bottom.


Attach CO2 bottle to the rigid garden tubing with a double male adapter and airline tubing. Begin flow of CO2
into the reactor.

There you have it! No more wasted CO2 from a bubbling airline tube injecting straight into your tank.

Start with 1-3 bubbles per second and adjust to best judgment.

Be careful though, I have found this reactor to be very efficiant so in no time at all you could have very high levels
of diffused CO2 in your tank which will be a major problem for fish.

Start Small.

Total Cost = $25.00 AUD
Pump = $14.95
Gravel Vac = $7.95
Bits and peices = $2.00

Author: Mark P.