Buffering and CO2 injection

'Michael A. Bateman' wrote:

I would disagree with you on this one.  I find it very useful to know ahead
of time when my bottle is about empty.  With the additional high-pressure
gauge, I get at least a week or two warning that the bottle is going "dry".
 I use CO2 to maintain a constant pH in my aquariums (in addition to
providing food for the plants)and if CO2 injection would cease for more
than a few minutes, my pH would start to rise quickly.  Since I keep fairly
expensive fish, this could prove expensive or at the very least stressful
to the fish.

I keep a spare 5 pound bottle around just to swap out with the 10 pound
bottles I use on the aquariums.  That way I can keep CO2 flowing constantly
and don't have to rush right out to get the 10lb bottle filled.

One thing I hate is pH flux. :)  

Greetings Michael,

I just lift the bottle to see how heavy it is, the bottle is quite light when nearly empty,
also you cannot hear the slopping around of the liquid as you can when it is full, or even
1/3 full.

I have found that the input pressure gauge, only moves in a few hours of the bottle 
completely emptying. If your pH rises dramatically if the CO2 stops, then possibly the
quantity of kH in the water to which the carbonic acid is reacting is too great. Talking to
a friend who designs and manufactures reticulating systems for aquaculture, suggests that
the quantity of kH being added should raise the pH to approx 0.5 to 0.8 above the level to 
be controlled. Bareing in mine that the systems that he is refering to are designed to hold 
upwards of  5 to 10 tonnes of fish/crayfish etc.

It may be different for smaller systems, but I cannot see why

Marque Crozman  -ANGFA-  NSW