There are only a handful of reputable tank manufacturers out there.
The specifications, tank pressures, dimensions, and materials for tanks are always being updated and changing. In some ways, they are changing drastically and in others slightly. It can be hard to figure out which ones will suit your needs.
In this article, we will go over the differences in tank pressure, and materials, and how to choose a tank.
We have also put our top five tanks in each category.
Just remember that there is no perfect tank or one tank for every situation.
How Does Tank Capacity Work?
You first should know how tank capacity works. The service pressure does not exactly correlate to the tank capacity.
All scuba cylinders have a relationship between their internal volume, their maximum service pressure, and the actual free gas capacity.
Without going deep into the math (click here for an in-depth breakdown) several tanks hold less air than the size advertised on the tank, so do your research.
Just remember the higher service pressure does not always mean more air.
- Ability to hold extra air
- Large range of colors
- Ability to use DIN & Yoke
- Large both length and width
- It is a heavy tank
This corrosion-resistant tank is really popular with divers. It is constructed from heavy gauge aluminum which makes it quite durable a is a goto tank for a lot of divers for good reason.
The company has been around for years and the quality of its products is why. The Sherwood C100 is a high-quality quality cylinder that comes in a range of colors so you can be visible and always find your tank.
The tank is negatively buoyant at 500 PSI because of the amount of aluminum it was made with. So make sure to think about this when weighting yourself as aluminum tanks are usually buoyant at the end of the dive.
For valves, it comes with a standard K valve that will work with a yoke, not a DIN but you can request a valve that allows for both a yoke and DIN. This is the largest aluminum scuba tank on the market.
- Convertible K-Valve for Yoke or DIN
- Heavy duty design
- Better for warm water
The Catalina 80cf Aluminum Scuba is another commonly used tank by recreational divers mainly since it is easy to use, durable, and lightweight. Catalina manufactures a lot of scuba tanks and the 80cf is the most common size they manufacture and the one you will see at diver with.
The working pressure of this cylinder is 3000 psi (200 bar) and is nitrox ready up to 40%. The great thing about aluminum is that it won’t rust like steel cylinders. It comes in 9 different colors as well so you can match your gear as well. is the deciding factor. The Catalina 80 Cubic Foot Aluminum Tank comes with their “Pro Valve” which means you can use a yoke or DIN valve easily by screwing and unscrewing the plug.
- Great Buoyancy
- Strong and Durable
- DIN and yoke compatible
- Steel can rust over time
This is Faber’s most widely sold cylinder as it has great buoyancy characteristics. When it is full it goes from -2.4 lbs. to -9.4 lbs. (-1.1 kg to 4.3 kg). The outer layer has a triple-protected finish to make it longer-lasting and more durable.
The working pressure for this cylinder is 3442 psi (237 bar) and passes the standards for DOT in the USA and TC for Canada.
You will need an O2 cleaning so you can use Nitrox up to 40%.
It also comes with the XS Scuba “PRO Valve” which is a yoke but is able to spin out and convert to a DIN valve.
Even though the price point for this tank is lower than most the XS Sxuba Metal Impact is still a cylinder you should highly consider. When new unlike most tanks it is ready for nitrox. It has a K-Valve that is set up for a yoke connector but by removing it you can connect your DIN connector.
The tank is durable, reliable, and lightweight. The tank is high-strength aluminum and has a 3000 psi (207 bar) service pressure rating (but only a capacity of 77.5 cu. ft. (11.1 liters)). The other nice thing about these aluminum cylinders unlike steel cylinders don’t rust.
- Can be filled with the hand/ electric pump, or the refill adapter
- Perfect for traveling
- Built-in pressure gauge for extra safety
- Can be connected with a high-pressure inflator
- It is a bit heavy
- Not meant for cold waters
- Maximum depth 33 feet (10 meters)
For safety when diving solo, in a wreck, or deep diving a pony bottle is an essential piece of gear that all divers should have. This little tank has a capacity of 1L and when fully inflated (depending on your breathing) will last you about 15-20 minutes.
With a weight coming in at only 5.07 pounds (3.5 kilos), a portable carrier is perfect for travel and transport.
When traveling on a plane you can also split the regulator and tank body to comply with airline regulations. There are also a few different options to purchase with a hand pump, different bags, and an electric air pump.
Things to Consider When Buying a Scuba Tank
Buoyancy & Materials
The two main choices in tanks are aluminum and steel, but carbon fiber is also there but less used. Aluminum cylinders are negatively buoyant at the start of your dive and usually positively buoyant at the end but not always.
This is something to think about when weighing yourself and controlling your buoyancy. While steel tanks are negatively buoyant from the beginning to the end of the dive and you can control your buoyancy easier with a steel tank. Steel will require fewer weights.
The manufacturing of compressed air tanks is not something companies can just do, nor do we want them to.
All air cylinders in the US, CA, and Europe have rigorous tests they must pass. The US Department of Transportation (USDOT) is the standard in the United States and is accepted in most countries around the world. Make sure the tank you buy or use has been certified by the country’s certifying agency.
Size and Air Capacity
As mentioned above size and air capacity are not always perfectly related. Scuba tanks come in a wide array of sizes for all the different types of diving.
The size shows how much air could possibly be compressed into the tank. The 80cf scuba cylinders are the most popular with adults, and the 63cf with kids.
If you use air quicker than normal or you want to dive deeper or longer a 100cf will work better.
Here is a quick guide for tank volumes:
- 10 – 30 cu ft: pony bottle
- 31 – 40 cu ft: stage bottle/redundant air source
- 41 – 63 cu ft: primary for a child
- 64 – 100 cu ft: primary for an adult
- 101 – 130 cu ft: primary for an adult/ tech diver
Valves play a major role in controlling the airflow from the scuba tank to your first stage. The K Valve is the most common one that you will see and should use. They screw in and usually come with an O-ring to make them watertight. Some of them have a “Pro-Valve” to make switching from yoke to DIN easy.
Yoke and Din Valves
In the past, the most common type of valve was a yoke K-valve usually found on aluminum and low-pressure steel cylinders. Now more divers are using a 200-Bar DIN valve that works in aluminum and low-pressure steel tanks. We have a full article here for you to read about these.
Paint, Coatings, and Finishes
These are all meant to stop corrosion and protect your tank but once water gets under the paint, corrosion is ok and encouraged. The paint colors can hide the corrosion underneath, so you want to see it.
The best aluminum tanks are unpainted. Unpainted finishes hold up better and do not encourage or hide corrosion while they may not look as nice as painted.
Uncoated steel tanks can rust quickly, so all steel tanks need to be coated with zinc. There are two zinc coating processes for steel tanks: dip and spray galvanizing. There is debate on which one is better.
Low and High Pressure
The pressure in a scuba tank is an average range from 2400 to 3500 PSI (165 to 240 bar). There are different reasons you should choose one over the other and we will go over them below.
Low-pressure scuba tanks
- Better for nitrox and technical divers.
- More common
- Easy to use
- Limited air capacity.
High-pressure scuba tanks
- Offers more breathable air
- Divers can stay underwater longer
- More difficult to use
Tips to Maintain Your Scuba Gear
Scuba tanks can last a long time, over 10 years if they are maintained properly.
Here are some tips to get the most out of your tank.
- Clean your tank with fresh water after diving to prevent corrosion.
- Never store your tank with an open valve or full of air.
- Store it vertically or horizontally.
- Clean your first-stage regulator to keep contaminants out of the tank valve.
- Never leave the scuba tank under direct sunlight
- Get a visual inspection once a year and a hydro test every five years.
Frequently Asked Questions
If you are diving in the pool this is a must. If you bump the tank on the bottom of a tile pool it can crack the pool. Other than that it is not necessary but is handy to keep it stable and gives it extra protection.
You are probably doing more than one dive a day, so you will need at least two or even three. It is not practical to get it filled between dives. Also, you may need different tanks for different types of dives.
Divers usually use them interchangeably so don’t worry about it. There is a slight linguistic difference but for official documents and requirements, it will say cylinders.
A scuba tank can last for 10-15 years. This will depend on the materials, and how you care for them.