What To Know About CO2 Tanks

Seltza is compatible with a variety of CO2 tanks/cylinders for carbonating water. You are not locked into a single size. Here are some common questions we get asked about CO2:

Where can I buy, refill or exchange CO2 tanks/cylinders?

You can obtain your CO2 from various suppliers. Here are a few options:

Beverage suppliers, such as home brew and wine making shops.
Hydroponic supply shops.
Local welding and gas suppliers.
Online retailers: Many online retailers sell CO2 tanks/cylinders, including Amazon, Home Depot and Walmart. Keep in mind that some retailers may not be able to ship CO2 tanks to certain locations due to shipping regulations, or will only ship empty tanks that then need to be filled.

Seltza provides a CO2 regulator which is compatible with threaded soda stream style canisters (TR21-4 threads), and an adapter for larger tanks such as 5, 10 and 20lbs (CGA-320 threads). Note, we generally don't recommend the small canisters as they are quick to empty and expensive to exchange.

What are the common dimensions of a CO2 tank?

Common sizes and specifications for CO2 tanks:

CO2 Tank Size	Diameter (in)	Height (in)	Empty Weight (lbs)	Full Weight (lbs)
2.5 lb	3.14	14.2	3.7	6.7
5 lb	5.25	18.2	7.5	15.5
10 lb	7.0	20.5	14.0	24.0
15 lb	7.0	29.0	20.0	32.0
20 lb	7.0	27.2	24.0	36.0
35 lb	7.0	34.0	43.0	61.0
50 lb	9.0	55.0	55.0	98.0

Note: Dimensions and weights vary. Check with your supplier for exact measurements.

What size CO2 tank should I buy?

Determine where you plan to place your CO2 and measure the available space. Note that your CO2 tank can be located 15+ feet from your Seltza Hub, so you have more options than just under the sink. By drilling a small hole for the 1/4" tubing line, you can locate it in a separate cabinet or the basement. If you plan to do this, contact hello@seltzatap.com for details on longer tubing.

Is CO2 safe to store in the home?

Here are some tips for safely storing CO2 in the home:

Store CO2 tanks in a cool, dry area. Avoid storing them in areas with direct sunlight or extreme temperatures.
Keep CO2 tanks away from open flames, electrical equipment and other sources of heat or ignition.
Make sure the CO2 tank is upright at all times.
Always follow manufacturer instructions for handling and storing CO2.
Do not attempt to refill or modify CO2 tanks yourself. This should only be done by trained professionals.

As long as proper safety precautions are followed, CO2 can safely be stored in the home for a variety of purposes.

What maintenance is required for my CO2?

When your CO2 has run out of gas you will be required to replace/exchange it. As the CO2 tank is connected externally, replacing it is a simple process.

The washer/o-ring inside the tank's CGA-320 regulator adapter also needs occasional replacement. Often people do this when exchanging their tank, or when a flow issue arises.

If gas is restricted but the tank is not empty, it's likely the CGA-320 washer/o-ring has been over-tightened or is in need of replacement.

If gas is escaping at the regulator, that's a sign the regulator needs to be tightened on further, or the washer/o-ring is in need of replacement.