Re: needle valves / Teflon tape

[zxcvbob <bob at area51online_net>]

Aquatic Plants Digest wrote:
> 
> Also, if you remove a taped fitting, you should take care that all the old
> tape is cleaned out of the threads and insides of both the male and female
> fittings before reusing them.  I keep a small wire brush around just for
> that purpose.
> 
> Generally, it's best to use pipe dope for gas fittings.  But folks
> shouldn't panic if they have used tape.  I have myself.  Just be aware that
> these problems can occur.
> - --
> Chuck Huffine
> Knoxville, Tennessee
 

Use "Rectorseal" brand pipe dope.  It is kind of expensive, but it is the
only brand I've found that doesn't seize up and maybe make the pipe joint
impossible to disassemble.

And just to register my opinion and probably piss off Joelle, any pressure
regulator should work just fine for low volume CO2, and if you have a
needle valve (or some other equivalent flow restrictor) the system will
never "dump" and you don't really need a check valve -- the water will
never back up past the needle valve.

I use an ancient welding O2 regulator refitted for CO2, and I change the
tank when it goes to 0.  The tank and regulator sits on the floor a good 4
feet below the water level in the aquarium.  No check valve.  No dumps.  No
problems.

Best regards,
Bob