Good CO2 check valve (was CO2 regulator problem)

["Joe Kopanski" <kopanski at earthlink_net>]

> I hope this helps. And, if anyone else reading this knows of
> a good check valve please let me know as I prefer to keep the gas cylinder
> and CO2 setup under my display tanks; which means they are potentially
> subject to water contamination.
>
I inject my CO2 into the output side of my filter system (which is all pvc
and is under the tank).  The filter is driven by a Rainbow Lifegard Quiet
One water pump.  This method is "invisible" in the tank and if you inject
contra to the water flow you get ~100% mixing (i.e. no bubbles in the water
entering the tank).  The pump pressurizes the line to about 5 psi.  I tried
4 check valves, the first three of which did not work in this extreme
application.

1)	Swagelok B-4C-1 Brass Check Valve ($15.20)  Though this was rated with a
1 psi cracking pressure, it didn't work worth a damn here.
2)	CO2 Injection Check Valve ($4.95) from Automated Aquarium Systems (This
is just an airline check valve)
3)	Dennerle Check Valve ($18) from Monolithic Marine Monsters
4)	German Air Pressure Systems Metallic Check Valve ($39) also from M3.
This is the one.  Still get a few inches of water up the CO2 line when the
CO2 has been off a long time, but the controller is 2 feet away.  By the
way, even connected in series, valves 1 plus 2 plus 3 didn't work.

http://www.marine-monsters.com/front/products/fp-co2accessories.html#metalli
c


Joe K
in parched Takoma Park, Maryland
where Cyclamen hederifolium are blooming in the yard (including self sown
seedlings through the dead grass!  Going to hate to mow.)