Co2 Tank Length Of Time To Empty?

[shadowhywind]

Hi all, I have a 5lb (small tank) of co2, I was wondering what is the normal(avg) time it should take to empty the tank, from previous searching I was lead to believe that it should last about 3-4 months. When I first picked up my tank I thought I got about 4-5 months, but since then every time I get it refilled I barely get a month out of it.
My setup: bubble counter I'm getting somewhere between 1.5 to 2 bubbles a second, the drop checker approaches yellow by the end of the cycle and no fish are gasping for air at the top of the tank. Co2 turns on an hour before the lights, and turns off an hour before the lights turn off. The lights are on for 9 hours.

Any thoughts would be great, thanks.

 

[GrayScale]

Hi all, I have a 5lb (small tank) of co2, I was wondering what is the normal(avg) time it should take to empty the tank, from previous searching I was lead to believe that it should last about 3-4 months. When I first picked up my tank I thought I got about 4-5 months, but since then every time I get it refilled I barely get a month out of it.
My setup: bubble counter I'm getting somewhere between 1.5 to 2 bubbles a second, the drop checker approaches yellow by the end of the cycle and no fish are gasping for air at the top of the tank. Co2 turns on an hour before the lights, and turns off an hour before the lights turn off. The lights are on for 9 hours.

Any thoughts would be great, thanks.

How new is the regulator? The Gage might be broken. When putting the regulator back on make sure it's nice and secure, there could be a very tiny leak from and of the connection ports. Or the place you go to to refill it is jipping you for your money and not filling up the tank all the way. I've read that a 5lb tank can last up to maybe a little longer than a year depending on the size of the tank.

How big is your tank btw?

 

[shadowhywind]

The regulator is almost a year old (picked it up in January). After reattaching it, I use some soap around all the connections to test for leaks. I have a funny feeling there not filling it up all the way, might just have to find someone a bit closer. The tank is also a 29 gallon

 

[waterdrop]

About how tall are 5lb cylinders? Are 10lb cylinders the next size up and and how tall are they?

Wouldn't you know from a gauge on your own regulator whether they've given you the full amount of CO2 it can hold?

WD

 

[Mikaila31]

About how tall are 5lb cylinders? Are 10lb cylinders the next size up and and how tall are they?

Wouldn't you know from a gauge on your own regulator whether they've given you the full amount of CO2 it can hold?

WD

Should know from the weight and the gauges if it is full or not. If you have a scale weigh it before and after filling. IMO though you are more likely to have a leak then anything. Also are you actually getting it filled or swaped?

 

[OldMan47]

Sorry WD. The weight of a cylinder determines how full it is. All cylinders of a given temperature and containing any liquid CO2 will register exactly the same pressure, saturation pressure for that temperature. On the other hand, a full 5 lb cylinder should weigh exactly 5 pounds more than an empty 5 lb cylinder. I run a 10 lb cylinder on a 40 gallon tank and maintain my CO2 levels just below the critical level of around 20 ppm. My 10 lb tank is empty after about 4 to 5 months so a 5 lb cylinder on a smaller tank like the 29 gallon should be lasting 3 or 4 months by my way of thinking. If it lasting much less than that, you have a leak that you need to find. One of the hardest losses to locate is probably the through wall loss that you will experience with ordinary tubing. There is no particular spot that will show bubbles using a soap test but it will be losing CO2 by osmosis along the whole length of the tubing.

 

[shadowhywind]

The place I Was going to refill the tank instead of swapping it out. I will have to weight it before and after I refill it to find out. But hopefully I wont be going back to them, I'd like to find a place a little closer to where I live. I remember reading somewhere when I was first thinking about doing the Co2 that the rubber hoses do wear out over time but I forgot what the 'average' time frame it was, any thoughts. I also remember reading something about the check valves would also 'break-down' after time, does that also happen with the glass check valves. I hate the bubble counter I have now, and I have seen some ebay auctions that have the bubble counter built into the diffuser and it comes with a glass check valve, if I go that route, I would end change all the tubing anyways.

 

[waterdrop]

Thanks OM, I keep forgetting that it's weight that tells you. In fact I ran across a lot of threads reminding that it's important for the place that fills your cylinder to have an accurate scale and that it's a good idea to know the weight of your empty cylinder accurately (the TARE weight) and to ideally pay attention that the attendent has filled accurately so that it's not over or underfilled.

I also found listing of typcial cylinder dimensions and made myself a file of it:

CO2 tank dimensions:

LB designation... height in inches... diameter in inches
2.5#... 14".........4.25"
5#.......18.25".....5.5"
10#.....20.5".......7"
15#.....27"..........7"
20#.....27.5".......8"

~~waterdrop~~