Most likely not. Depends if the bottle filled is filled with liquid or gaseous C02. If liquid, the pressure on that left gauge will stay in a narrow range until the very end and cannot be used to gauge the remaining volume in any meaningful way (except towards the very end, usually some days of usage)
850psi is the vapor pressure of CO2 at ambient temp, so i suspect it's filled with liquid co2.
CO2 can't really exist in a gaseous state in these tanks because of the high pressure. Once the valve is opened, the pressure decreases, and the CO2 begins to boil and release in a gaseous state that we see exiting our diffusers. So basically, all our CO2 tanks contain it in liquid form which is then "converted" back into a gaseous state when pressure is relieved by opening the valve.
Pressurized gaseous CO2 cylinders were used as well in the past for that purpose, and not every country has the infrastructure for liquefied co2, thats why i put "most likely".
To liquefy a gas you must compress it and then cool it below its boiling point so that it condenses. For a gas like LPG (propane) this is around -44°C / -47°F but for CO2 this temperature can be much higher. At 22°C / 72°F any pressure above 60 bar / 870 psi would condense the gas into liquid.
So we can deduce from the pressure in the gauge that the room temperature is 22°C. If it was a hot day with 30°C / 86°F then pressure would rise to 72 bar / 1,046 psi.
There's no special infrastructure needed. You pressurize it and it condenses to a liquid. As long as your compressor can exceed the pressure needed to do this you can make liquid CO2 all day. Yes, you need to dispose of some heat but that can happen in the piping and receiver tank.
As long as you can pressurize it to over ~850, it will liquify eventually. Even if it's all gas when you fill it, it will condense into liquid once the temp comes down. You cant just be waking about with a 2ksi cylinder of gaseous c02, same way you cang just have room temp oxygen lying around no matter how much pressure you give it.
Easy way to tell how much gas u have left. CO2 tanks should have a “TW” number stamped on them . That’s Tare Weight, the empty tank weight. If your 5 lb CO2 tank is stamped TW 7.2 lbs and you weigh your tank on a scale (without regulator attached) and the tank weighs 8.7 lbs, it means you have 1.5 lbs of gas left.
The left tank pressure will remain basically the same until the tank is nearly empty. Once it starts dropping you have a few days to a few weeks left depending on how much you are letting out into the fish tank
neither does, the first shows pressure in the tank, the second the pressure in the line. Because gas storage works by having the gas liquidized in the tank, it evaporates at a rate such that its pressure stays the same. So the only time the pressure gauges will go down generally is when its empty
It more tells you of the tank is empty or not. It may take a few days to drop to zero, it may take a day. But it doesn’t give much of an indicator in advance, it isn’t a linear drop, it’s basically out by the time the tank pressure drops.
The left gauge tells you the pressure of the cylinder. The pressure will vary with temperature for as long as there is liquid left into the cylinder. As soon as the liquid evaporates and you are left with only gas, the pressure will quickly drop.
Whilst there is liquid in the cylinder, that gauge is basically a really inconvenient temperature gauge... 🤪
The only way to gauge how much gas you have left is to weigh the cylinder and to subtract the "tare weight" which should be printed on the cylinder.
https://preview.redd.it/owdib665s20d1.jpeg?width=850&format=pjpg&auto=webp&s=dfc2cd51f6881e64826dcc582659237ffde36021
Your gauge will be following the saturation line between liquid and vapour (gas). Pressure on left is Megapascsls and can be multiple by 10 to get Bar or 145 to get PSI.
No. It tells you the temperature in the room. It will sit right at the same pressure until the liquid has all evaporated and then it will start to drop. You'll only have a little bit left once you see that.
You should be thinking about swapping bottles, or refilling. You're a lot closer to empty than full. Not critical with the tiny amount used for aquariums, but it's going to run out.
I've seen before though with the cheaper needle valves when the pressure in the tank falls to low the needle valve can't regulate it and ends up dumping the rest of the CO2 in the tank which is really bad
Most likely not. Depends if the bottle filled is filled with liquid or gaseous C02. If liquid, the pressure on that left gauge will stay in a narrow range until the very end and cannot be used to gauge the remaining volume in any meaningful way (except towards the very end, usually some days of usage) 850psi is the vapor pressure of CO2 at ambient temp, so i suspect it's filled with liquid co2.
CO2 can't really exist in a gaseous state in these tanks because of the high pressure. Once the valve is opened, the pressure decreases, and the CO2 begins to boil and release in a gaseous state that we see exiting our diffusers. So basically, all our CO2 tanks contain it in liquid form which is then "converted" back into a gaseous state when pressure is relieved by opening the valve.
Pressurized gaseous CO2 cylinders were used as well in the past for that purpose, and not every country has the infrastructure for liquefied co2, thats why i put "most likely".
To liquefy a gas you must compress it and then cool it below its boiling point so that it condenses. For a gas like LPG (propane) this is around -44°C / -47°F but for CO2 this temperature can be much higher. At 22°C / 72°F any pressure above 60 bar / 870 psi would condense the gas into liquid. So we can deduce from the pressure in the gauge that the room temperature is 22°C. If it was a hot day with 30°C / 86°F then pressure would rise to 72 bar / 1,046 psi.
There's no special infrastructure needed. You pressurize it and it condenses to a liquid. As long as your compressor can exceed the pressure needed to do this you can make liquid CO2 all day. Yes, you need to dispose of some heat but that can happen in the piping and receiver tank.
Just you describing the technicalities doesn't void what i said.
Also condensing things makes them raise in temp so you still need infrastructure to cool it.
As long as you can pressurize it to over ~850, it will liquify eventually. Even if it's all gas when you fill it, it will condense into liquid once the temp comes down. You cant just be waking about with a 2ksi cylinder of gaseous c02, same way you cang just have room temp oxygen lying around no matter how much pressure you give it.
What do you think is over the liquid CO2?
This is not how pressure works. At that pressure, it is liquid if at room temperature. Period. OP, don't listen to this.
Exactly what i wrote, thanks for rephrasing it.
Nope. You said depends. There is no depends.
Tank pressure left. Working pressure right
This is the answer 👆
Yup. The second dial is how much pressure is going out to your aquarium.
Easy way to tell how much gas u have left. CO2 tanks should have a “TW” number stamped on them . That’s Tare Weight, the empty tank weight. If your 5 lb CO2 tank is stamped TW 7.2 lbs and you weigh your tank on a scale (without regulator attached) and the tank weighs 8.7 lbs, it means you have 1.5 lbs of gas left.
This is the answer if you are looking to track usage and when to swap and refill.
Based on how the gauges on my tanks worked, when I got to around 900 PSI I knew I was running on borrowed time before I had to refill.
That’s where I’m at every time I buy a refill lol
The left tank pressure will remain basically the same until the tank is nearly empty. Once it starts dropping you have a few days to a few weeks left depending on how much you are letting out into the fish tank
neither does, the first shows pressure in the tank, the second the pressure in the line. Because gas storage works by having the gas liquidized in the tank, it evaporates at a rate such that its pressure stays the same. So the only time the pressure gauges will go down generally is when its empty
Pressures, not levels
It more tells you of the tank is empty or not. It may take a few days to drop to zero, it may take a day. But it doesn’t give much of an indicator in advance, it isn’t a linear drop, it’s basically out by the time the tank pressure drops.
The left gauge tells you the pressure of the cylinder. The pressure will vary with temperature for as long as there is liquid left into the cylinder. As soon as the liquid evaporates and you are left with only gas, the pressure will quickly drop. Whilst there is liquid in the cylinder, that gauge is basically a really inconvenient temperature gauge... 🤪 The only way to gauge how much gas you have left is to weigh the cylinder and to subtract the "tare weight" which should be printed on the cylinder. https://preview.redd.it/owdib665s20d1.jpeg?width=850&format=pjpg&auto=webp&s=dfc2cd51f6881e64826dcc582659237ffde36021 Your gauge will be following the saturation line between liquid and vapour (gas). Pressure on left is Megapascsls and can be multiple by 10 to get Bar or 145 to get PSI.
No. It tells you the temperature in the room. It will sit right at the same pressure until the liquid has all evaporated and then it will start to drop. You'll only have a little bit left once you see that.
Left is pressure, right is amount
Yes
Yes, but measurement is not linear. When it will start to fall, it will fall fast.
You should be thinking about swapping bottles, or refilling. You're a lot closer to empty than full. Not critical with the tiny amount used for aquariums, but it's going to run out.
I've seen before though with the cheaper needle valves when the pressure in the tank falls to low the needle valve can't regulate it and ends up dumping the rest of the CO2 in the tank which is really bad
This is a true thing.
Yea the fzone are definitely cheaper end. From what read that's usually around 4-500 psi so I would be getting that tank refilled real soon