[FSM]

The plastic check valve I have seems to be leaking. It is attached to the air tube right before it enters the CO2 diffuser (rex grigg style).

So I am going to buy a brass one.

I can either get a clippard check valve which costs about $14, or I can get one off ebay for $5 from malaysia. http://cgi.ebay.com/High-Grade-Bras...in_0?hash=item1c07f1e06c&_trksid=p3286.c0.m14

Has anyone used those?

 

[Wasserpest]

Cheap check valves might fail down the road. Especially those that are made for air pumps. The water/CO2 mixture turns into carbonic acid that will corrode regular (air) check valves over time. I'd suggest to go with one that is spec'd for CO2.

I have been using one of these for over five years without problem. Not cheap, but not only does it protect the expensive reactor/needle valve, it also provides peace of mind knowing that it will not fall apart and empty my aquarium through the reactor while I am away...

 

[FSM]

My primary worry is 50 gallons of water on the floor.