Only did this, because as you know, the pressure of the tank stays 800psi/55bar odd during its "life". This is because pressure above the liquid CO2 stays constant, so you cant use tank pressure to gauge how much CO2 you have left.The tank pressure only drops when liquid has all gone, in which case I have a couple of days usage left. Weighing means you have much greater notice tank is getting empty and you can pre-empt and change during water change time. I find 100-200gr left is when I change the tank. Easy peasy.Great idea @ian_m !
Or drill one .....
FWIW - Found out what the problem was with CO2 Supermarket. In short, they only take a certain number of orders each day to ensure they meet their service level for despatch. In reality it seems you have to place your order the day before (i.e not by "3pm") to get "same day" (actually next day) despatch. 3pm is the deadline but apparently the order threshold is normally met by 7pm the night before. You can't even place the order - checkout simply goes to a blank page. So... plan ahead!
I bought one from personal recommendation from ebay, the label on it says Aqua Labs, and I set it up yesterday. I am worried that it only has one dial on, and some have 2, some have none. I am presuming that the reading on the dial I have is the pressure that the gas is at in the FEcylinder. Have I understood this correctly? If so, do I need to watch it for drops in pressure, and would a drop signal the end of the cylinder and time to buy another?
They do have the weight stamped on them, but this is the weight without a regulator (or horn if an FE) and is used for filling as they fill by weight not volume. Obviously once a regulator is attached it is much heavier than the stamped weight, which is why you have to write your own values.most cylinders will have a imprint of the empty weight of the cylinder
They do have the weight stamped on them, but this is the weight without a regulator (or horn if an FE) and is used for filling as they fill by weight not volume. Obviously once a regulator is attached it is much heavier than the stamped weight, which is why you have to write your own values.
Normally if a regulator has only a single gauge it would be the working pressure gauge - essentially the pressure coming out of the regulator not the tank pressure. A quick look would confirm which one it is:
In this case one option is to use the handy trick ian_m mentioned by measuring the cylinder weight as it progresses, most cylinders will have a imprint of the empty weight of the cylinder, once it gets relatively close to this value you should consider replacing the cylinder.
- If the PSI numbers are in the hundreds to thousands the gauge is tank pressure.
- However if the PSI numbers are in the tens to hundreds the gauge is the working pressure.
As far as a drop of tank pressure this would signal the cylinder is coming to the end of its supply, depending on your bubble rate you could expect anywhere from a few hours to a few days remaining. This is because as mentioned by ian_m again that tank pressure will remain stable until the liquid runs out, only then will it begin to drop and you're left with the gas remaining in the cylinder. Without a second dial reading tank pressure it is hard to use this method though.
The gauge starts at 500 then goes up in thousands, so I guess its tank pressure. The needle is just past the 1000 mark. I need to weight it I suppose.
As this is my first CO2, when your bottle does run out, do you need to unfasten the tape on the tank handles and then unscrew the regulator, just in case there is more in there than you thought? Or do you just unscrew the regulator and nothing happens?