# pros/cons of a 20# cylinder?



## shrimpy1 (Mar 29, 2006)

Hi All,

I'll be getting my first pressurized CO2 system soon. I'm weighing the options for co2 tanks, 5# vs 10# vs 20#.

I can get a 20# for $20 more than a 10#, which in turn is $20 more than a 5#.

I figure getting a cylinder as large as possible will a) last longer between fills and b) reduce maintenance effort and costs (it's a drive to a good nearby refiller). That being said, what are the strikes against a big 20# tank? Also, how much does a filled 20# tank weigh?

TIA


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## BryceM (Nov 6, 2005)

I just picked up a 20 lb cylinder today. If you're worried about weight, it's certainly heavy - not so much that you can't move it, but a trip up 3 flights of stairs would get old. An aluminum tank would be better if you can find one.

From what I've been told, gas suppliers keep 20 lb cylinders in their inventory regularly, but 10 lb tanks can be hard to find. If your place refills the tanks, then it's no issue, but if they only exchange tanks you might have a harder time finding a 10 lb tank in-stock.

My 5 lb tank lasts >6 months on my 46g aquarium (on 10 hours per day). I opted for a 20 lb tank for the 180g tank to stretch out time between changes.

My cabinet is almost 29" high inside. The 20 lb tank with regulator will just barely fit. Keep that in mind too.


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## wiste (Feb 10, 2006)

> how much does a filled 20# tank weigh?


I believe the weight is around 20 lbs. Feels like 20 lbs. when lifted. So, not that heavy.
The only strikes are if it does not fit into your cabinet and possibly initial cost.
Only 20 dollars more than a 5-lb tank sounds like a good deal.
I went with a 20-pound tank for a 75-gallon.
My 5-lb tank lasted 3 months on a 35-gallon tank that was not sealed and was running 12 hours per day.


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## redstrat (Apr 3, 2006)

so what would be the average overall height of say a standard 20# tank with a millwaukee or azoo regulator attached?


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## Rex Grigg (Jan 22, 2004)

A 20 lb tank holds 20 lbs of CO2 so they must weigh more than 20 lbs. My steel 20 lb tank comes it right about 48 lbs filled.

An aluminum tank would be around 35-40 lbs filled.

There is actually no "average" height as there are no standards on CO2 cylinders. My 20 lb cylinder is 26". You can mount a regulator on a cylinder so that it basically adds no height to the cylinder. If you build your own regulator or buy a custom built one it will add NO height to the cylinder.


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## Rupey (Jun 3, 2004)

I'm not sure if its like this everywhere but where i exchange my 20 tank it costs $17.86 with tax. Last time I went in they didn't have a 20 so I had to get a 10 lb tank. Price was $16.56! Thats why I use a 20 lb tank


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## turtlehead (Nov 27, 2004)

Size and weight, are factors to consider. Shrimpy, if you are going to next SCAPE meeting, maybe you could arrange something with Mike(turbomkt) to pick up a CO2 bottle for you at breveragefactory.com it was cheaper than anywhere else I looked, and if you need it quicker, it can be shipped for a low price. I had it arranged with Mike last time for the meeting at Carl's. And I'm not sure when the next meeting is, I'm working on it though.


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## redstrat (Apr 3, 2006)

I guess my height question really is how much does the Millwaukee regulator add to the overall height. This has always been a concern for me so I was really happy to see someone talking about 20# cylinders. I have a taller than normal stand because I built it that way on purpose but I'm still a little concerned about ease of changing the cylinder when I go pressurized. Not trying to hyjack this post but I have one other question while on the subject. I have a closet right next to my aquarium that has my furnace and hot water heater in it, it can get a little warm in there in the winter time(probably 90+ degrees F). If the tank wouldn't fit in my tank I always figured I could put it in there but I was concerned about the warmer temperatures affecting the cylinder, is this even a concern in this range?


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## TWood (Dec 9, 2004)

Here's my 20LB cylinder next to an Eheim 2028. The measuring tape is at 27" to the top of the regulator gauges/tank valve handle. But it depends on how the regulator is set up.


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## redstrat (Apr 3, 2006)

wow thanks for the pic I see what your saying now.


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## shrimpy1 (Mar 29, 2006)

Thanks all. I've decided and just placed an order for a 20# alum. tank at beveragefactory.

I'm also planning to get the AZOO co2 regulator set from petwarehouse.

CO2 Pressure Regulator w/Solenoid

I'm planning to run the co2 line into my filter, so I won't need a diffuser.

Is there anything else I need? 
I already have blue silicone tubing, but I heard it's not very good?

Thx


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## redstrat (Apr 3, 2006)

Maybe a bubble counter and some CO2 tubing, this will not leak like the blue silicone. Although the silicone will be fine temporarily.


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## turtlehead (Nov 27, 2004)

Yes, you'll also need a bubble counter.


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## TWood (Dec 9, 2004)

turtlehead said:


> Yes, you'll also need a bubble counter.


No you don't. Place the end of the CO2 tubing in the filter strainer so you can see it. There's your bubble counter. You'll also likely be able to hear each bubble as it hits the the impeller anyway. Adding a bubble counter just adds several more places the CO2 system can leak.


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## redstrat (Apr 3, 2006)

good point but you can't always see the filter intake when the plants are grown in. Also depending upon filter design you might not hear each bubble hitting the impeller as you could hear several or none if the impeller is toward the output of the filter and the bubble dissolve or are to tiny to hear by the time they get there.


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## Rex Grigg (Jan 22, 2004)

Once again. You can mount any regulator horizontally and it will add little to nothing to the cylinder height.

90 degrees is a bit warm. But my house has gotten that warm a few times this summer.


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