How To Make A C02 Reactor For Planted Aquarium?

[joyboy]

I want to make a co2 reactor/diffuser for my aquarium, I saw the yeast ones online but they don't seem "Long Term". I wanted something that will last. I saw on the forums somewhere you can make one using a co2 fire extinguisher and you only have to replace the cylinder once or so a year. How do i make one, I need the complete instructions, equipment needed etc.
Any better ideas welcome as well!

 

[DrRob]

You need a regulator, a bubble counter, a needle valve, some tubing, a check valve, some means of diffusing into the aquarium water and, of course, a CO2 fire extinguisher.

There are some pretty good instructions out there if you google them. I can't get google to work right now, my work computers are playing up royally.

 

[OldMan47]

I bought a simple regulator / solenoid for one of my tanks and set it up to use a standard CO2 cylinder. It turns out that a 10 pound cylinder of gas lasts me about 6 months in that application and it costs me about $13 to refill the cylinder. There are plenty of places set up to refill a CO2 bottle since they are used in both welding applications and in soda machines in restaurant locations. In almost any decent sized town, you can get a CO2 bottle refilled at a welding gas supply house.
A fire extinguisher can indeed be used in place of a standard gas bottle but I am not sure it saves you anything. Have you ever seen how huge a 10 lb CO2 extinguisher is? Compared to the 18 inch tall bottle that I use, it is enormous. The next issue is the need to hold the installed extinguisher valve open at all times. That can be done using a tie wrap (cable tie) to hold the hand operating valve depressed but I find it much nicer to be able to simply open a valve intended to actually control flow, not one designed to dump the contents on a fire. My own opinion, and it is strictly my own, is that I would rather buy equipment designed to be used with a regulator than hope that I can get a fire extinguisher to work with enough adapters. The bottle, even full, is not very expensive.

 

[DrRob]

To be fair, at least in the UK. CO2 fire extinguishers fit standard refillable gas bottle regulators without the need for an adaptor. The thread for the nozzle is the same standard.

 

[OldMan47]

In the UK that would make things easier. In the US that is not the case at all. Who knows what the case may be in Australia then.

 

[DrRob]

This would explain why the set ups are less popular in the US.