Once diving becomes a serious hobby, you might be interested in buying your own compressor for filling your tanks. There is nothing wrong with dive shops, but there’s nothing like being able to fill up your tank wherever you are.
Scuba divers are putting their lives at risk every time they enter the water. Their air tanks are designed to help them breathe underwater. However, if they run out, they can’t breathe. This is why it’s so important that they are given a constant airflow.
When you choose a scuba air tank compressor, it needs to be specifically made for diving. Unless the compressor delivers clean breathing air at high pressures, you risk injury or death when you dive.
Something that many people don’t understand is that you can’t fill a scuba tank with just any air compressor. Some scuba tanks are filled with pure oxygen, but there are serious risks to them and it’s not recommended. Most oxygen tanks only have 20.9% oxygen, mostly for decompression.
This article will go over two compressors for filling SCUBA tanks and two compressors for SNUBA diving. You cannot use the SNUBA compressor for SCUBA diving, so you must choose one or the other depending on what type of activity you are performing.
Top Scuba Air Compressors
1. Alkin W32 Silent Canopy Scuba – High-Quality Breathing Air Compressor
Alkin has been in the high-pressure compressors market since 1990. Along with a line of scuba breathing air compressors, they also manufacture compressors for paintball, air guns, and fire and rescue operations.
The scuba line of compressors falls into two groups—Canopy and Mariner.
The W32, W3, and W4 Silent Canopy are larger units best suited for filling stations. The W32 is the smallest unit, but at 640 pounds, there’s nothing portable about it.
Alkin has two portable air compressors—the W31 and W32 Mariner.
Alkin W32 Mariner
The W32 Mariner, at 20 inches wide, 44-53 long, and 27-32 high, is on the large side of portable scuba compressors and on the heavy side. The lightest model weighs 364 pounds, making the unit better suited for use on a boat.
You can purchase a gas or electric power, and the power range is from 7.5 to 13 horsepower. All models have a max psi of 5,000, and the fill rate is either 250 or 300 liter per minute.
Most importantly, air quality is Grade E and D.
- Safety valves
- Oil pressure switch and gauge
- Overload protection for the electric motor model
- Two filling hoses
- P41 purifier with refillable purifier element
- 2nd and 3rd stage water condensate and oil separator
An automatic start and stop is an optional feature; however, it should be a standard feature with a scuba compressor.
Alkin 31W Mariner
For true portability, check out the Mariner 31W. It is a compact 17 by 32 by a 20-inch breathing air compressor (the gasoline models are 41 inches long). Not only does it weigh 143 pounds, but the 31W also has a vertical option that comes with wheels, allowing for greater mobility.
As with the 32W, the 31W has similar key features:
- P21 purifier
- 2nd and 3rd stage water condenser and oil separators
- Safety valves for each stage
- Overload protection for electric motor
- Grade E or D air quality
The 31W has only one filing hose, as one would expect from a genuinely portable compressor. The hose comes with necessary yokes, valves, adapters, and pressure gauges.
Again, Alkin makes the automatic start, and stop is an optional feature? Still, if you are looking for a portable, relatively lightweight breathing air compressor, the Alkin W31 Mariner is a good option. The starting price will be around $3,000.
2.Max-Air 35 – Small Scuba Air Compressor
We chose this air compressor for filling scuba tanks as our best portable option because it’s compact, lightweight, and can fill an 80 cu ft scuba tank to 3000 PSI in 19-22 minutes.
As we mentioned earlier, a compressor used to fill scuba tanks needs to have a high enough PSI. The Max-Air has a maximum PSIG rating of 5800 and can fill an 80 cu ft scuba tank in 19-22 minutes. The timing actually varies depending on the power source being used. This particular compressor is economical and easy to maintain.
It has an oil/water separating chamber and tri-chemical breathing air purification system with an activated carbon/molecular sieve. The disposable purification cartridge is a breeze to replace.
The compressor has a CFM rating of 4.2 and a 5.5 hp Honda motor. We felt that it performed very well and filled up our scuba tanks quickly and quietly. Since it weighs around 85 pounds, it’s portable enough to go where it needs to go.
It has convenient carry handles attached to a durable powder-coated steel frame for maximum longevity. We didn’t think the compressor was too loud when compared to others and is rated at 87dB.
The model compressor comes equipped with a digital hour/tachometer whereas other models come with only a digital hour meter.
The compressor is air-cooled and four-stage with four-cylinder high-pressure, non-continuous duty. We thought that the automatic/adjustable pressure shut-off switch was a nice addition as well.
What We Like
- High PSI rating
- Quiet 87 dB compared to others
- Quick fill time
- Durable steel frame
- Tri-chemical breathing purification system
What We Don’t Like
3. Quincy 5120 – Best Commercial Scuba Compressor
We chose the QUINCY 5120 as the best commercial scuba compressor because of its powerful 37.4 hp Kubota engine and 96 CFM rating.
If you plan to do a lot of scuba diving and don’t want to have your tanks filled by your local scuba shop, the Quincy 5120 will certainly do the trick. It’s not cheap by far, but it’s one of the best 2 stage commercial scuba compressors on the market. It has a powerful 96 CFM @ 175 PSI flow rate, which equals around 2690 Liters per minute.
The Quincy 5120 has Grade D breathing air, which has an Oxygen content of 19.5-23.5 percent. As you may know, scuba tanks require at least 20.9% oxygen content. We thought that the compressor filled our scuba tanks quickly. At 2690 Liters per minute, it filled our 80-gallon cubic foot tank in just about one minute.
The compressor itself has a 15-gallon fuel tank for Diesel input and a 60-gallon volume air tank. It’s very simple to operate and the heavy-duty powder-coated offshore frame with vibration isolated inner frame reassured us that it was a durable machine. There’s a full instrument panel and the engine is water-cooled.
What We Like
- Fills tanks quickly
- Grade D breathing air
- Powerful CFM rating
- Ideal PSI
- Durable construction
What We Don’t Like
- It’s very expensive
- Super heavy
Because they are designed and built in Germany, all portable models—the Dive Mate, Junior II, and Oceanus—have diesel, electric, and gasoline-powered models.
The Dive Mate model is rather heavy—at either 136 pounds for the Size 8 model or 181 pounds for the size 10. However, both sit on a wheeled frame so that you can roll it in place.
These scuba compressors have several standard features that the other compressors either do not have or as optional features, including
- Vibration isolators (for quieter operation)
- High-temperature switch
- Visual indicators for moisture and CO
- Hour meter
The fill rate is 238 liters per minute for the Model 8 and 275 liters per minute for the Model 10. The Model 8 is rated to 5,000 psi, while the Model 10 has an impressive 6,000 psi.
Bauer takes quality breathing air seriously and has developed a patented filter that uses UVC light to destroy pathogens before they can enter the scuba tank. They are rated for 2,000 hours of use. These filters must be retrofitted on older Bauer models.
Junior II and Oceanus—True Portability
If you want true portability, these two models are the lightest true scuba breathing air models. The Junior model weighs between 40 and 75 pounds, while the Oceanus is four pounds heavier.
Both models come in a variety of packages, depending on the fuel source. All are 3 stage compressors and have a standard Bauer filtration system. The Junior models have a lower fill rate (in the 82 to 122 range). All the Oceanus models have a fill rate of 139 liters per minute and can fill two cylinders.
Bauer’s Junior II and Oceanus are the only compressors that include a yacht package. Because of the large oil sump, these compressors have the highest inclination at 30 degrees.
Bauer’s do not come cheap. Expect to pay around $6,500 for the Oceanus and over $10,000 for the yacht packages. The Junior II is comparatively a bargain at approximately $5,000.
Air Compressors For Snuba Diving
snuba diving is a mix between snorkeling and scuba diving and requires a different type of breathing apparatus.
Snuba divers don’t wear tanks, rather, a simple mask that’s hooked up to an air hose attached to a compressor above the water.
It’s more for applications where snuba divers wouldn’t be as deep of water and therefore wouldn’t require a heavy oxygen tank.
5. Brownies’ Third Lung Diving System – Best Floating System
We chose the Brownies’ Third Lung Diving System as our best overall floating system for snuba diving because it’s lightweight and provides 3 hours of runtime per tank.
This is a great little system to have if you plan to do some shallow snuba diving. This system has a 4.0 hp 4-cycle Honda engine. It can provide divers with 3 hours of run time per tank of gas. The wonderful part about this system is that it frees you up from the heavy tanks that traditional scuba divers wear. It can accommodate two to three divers to 33 feet or if you upgrade to the PRO package, it can accommodate 2 divers to 65 feet.
The system is pretty lightweight, coming in at only 44 pounds with the compressor in the storage case. It would be pretty simple to transport on and off of a boat. The setup comes with a 7-foot heat hose and an easy-to-clean line particle filter. The compressor itself is a single head direct drive oil-less setup for easy maintenance.
One feature we really appreciated was the flag. It seems silly, but it’s very helpful in case of an emergency. The flag shows people that you’re diving and potentially still under the water. It also gives you an idea of where you are if you seem unsure while you’re under the water.
What We Like
- Flag for better visibility
- Conveniently portable
- Easy to maintain
- Generous swim line
- Other options available
What We Don’t Like
- It’s pricey
6.HPDMC 550W Dive System – Best Electric Dive System For Boats
We chose the HPDMC 550W Dive System as the best for boats because it can supply unlimited air and can support one diver up to 98 feet and two divers up to 32 feet.
We really like the HPDMC 550W Dive System for many reasons. First, it can run continuously. All you need to do is ensure it’s hooked up to a power source and it will run as long as you want it to.
It has an overheat protection device that will control the temperature of the motor if the temperature rises. However, it’s advised that you turn it off once in a while to avoid added stress on the motor.
This unit has a Diaphragm Air compressor that aids in air pressure compression to 2.5 bars. It also comes with a filter that filters the air when it’s compressed. The two-way air compressed purification and filtration system is perfect for a variety of divers. It comes with a 50 ft hose, but with an additional hose, it can support two divers up to 32 feet and a single diver up to 98 feet.
The receiver tank is 10 liters and made from stainless steel for rust resistance. It’s an oil-free pump, so there’s no need to add oil for lubrication. It has a flow charging rate of 60L/min and 2.0 CFM. We think that this would be the perfect dive system for boats since it weighs just 18.6 pounds. It can be easily transported from boat to land if needed.
What We Like
- It’s lightweight
- Can provide continuous run time
- Has overheat protection
- Supports multiple divers at outstanding distances
- Easy to maintain
- Two-way air compressed air purification and filtration system
What We Don’t Like
- Overheating will reduce the lifespan of the motor
Why You Should Buy a Compressor for Your Scuba Tank
As you transition from being an occasional, weekend diver to a serious one, you might want to buy an air compressor. The two most important reasons to buy a scuba air compressor is portability and saving time.
- If you are at a dive site and want to take a lunch break before your afternoon dives, you don’t need to hike back to the shop to refill your tanks.
- The dive site is not close to a shop.
- You and a couple of your diving buddies want to pool your resources and have a portable compressor.
A beginning diver might want to make sure they will stick with it long enough to offset the investment of a scuba compressor. When you finally decide to get a compressor, make sure it is designed for diving.
Should You Use Regular Air Compressor?
You should only use an air compressor designed to fill scuba air tanks. Divers rely on the air to breathe, so a compressor needs to do two things—provide breathable oxygen at high pressure.
The Need to Filter the Air
To provide the diver with breathable air, scuba compressors rely on a filtration system that does the following
Remove moisture and oil in the air. Water needs to be removed from the air because a diver cannot breathe it. Also, water cannot be compressed, and a scuba tank needs to be highly pressurized. A separate issue is that water can also cause the tank to rust.
Eliminate poisonous gas. The compressor must remove toxic carbon monoxide and bring carbon dioxide to safe levels. The filtration system oxidizes carbon monoxide (CO) and converts it into CO2. Activated carbon filters and molecular sieves in the system are used to reduce the level of carbon dioxide.
Most air compressors for scuba tanks use a combination of an air dryer, water traps, and filters to remove moisture and deliver breathable air. The filtration system is complex–check out the diagram of a scuba air compressor’s filtration system to see how the different parts work together.
The Need to Pressurize the Air
A scuba tank needs to be filled to around 3,000 psi (pressure per square inch), which a regular compressor cannot do. High pressure is required so that scuba diver can expand their lungs to breathe underwater.
Remember that any gas moves from a high to a low-pressure space. When you blow into a balloon, it fills up because the pressure inside it is higher than the air pressure around it. Now imagine that the balloon is in a box. You would be able to blow the balloon until it filled the box and no more because the pressure you can exert is less than what is needed to break the box.
Even though it is not a solid, ocean water exerts more pressure than the atmosphere, and the pressure increases as depth increases. To compensate, the air coming from the diving tanks needs to be higher than the pressure of the water. Otherwise, a diver will not be able to breathe in air.
Higher pressure in a tank gives the diver more time to be underwater. A recreational tank that holds 80 cubic feet of air at 3000 psi holds the amount of air that would fit into an eight by ten room.
For those two reasons, diving tanks need to be filled with a scuba air compressor.
Can You Breathe Air From A Regular Air Compressor?
Air from an air compressor is not meant for breathing. This type of air is not suitable for human breathing unless air treatment is significant and sufficient. However, there are certain compressors created specifically to produce breathing air.
You can’t breathe from a regular air compressor because there are many nasty particles and other things that can get into the air stream such as oil, tank coating, and other airborne debris.
As compressors generate water as air is compressed into the tank, the water mixes with all of the gunk that is already in the tank and is pushed through the air stream. You certainly don’t want to breathe this in.
Can You Use A Regular Air Compressor To Breathe Underwater?
You cannot use a regular air compressor to breathe underwater since it is significantly different for underwater use.
Scuba compressors are high-pressure compressor systems that are designed to fill tanks that scuba divers use for breathing underwater. A standard air compressor wouldn’t provide the adequate air that a scuba compressor can.
If you are snuba diving, then you can use an air compressor that’s specifically meant to supply you with adequate airflow. These are not meant to fill tanks, rather, they use an air hose that allows you to hook up directly to the special compressor for a certain amount of time before needing to either come up for air or shut the compressor off.
How Does a Scuba Air Compressor Work?
Diving air compressors for scuba and hookah diving are battery or gas-powered compressors that deliver air through a hose called a down-line. This hose is hooked to the diver that allows them to breathe. Gas-powered compressors generally have a 3 to 3.5-hour tank supply to more than one diver at a time, depending on the size.
Hookah diving doesn’t require the use of a BCD or first-stage regulator. The diver will wear a harness that the down-line attaches to.
The harness is worn on the diver’s back and keeps the hose out of the way. It also prevents the regulator from being removed from the diver’s mouth. There’s also a weight belt that counteracts your body’s natural buoyancy to make the control of depth easier.
What Is A Breathing Air Compressor?
A breathing air compressor is meant for snuba or hookah diving. It’s a mix between snorkeling and scuba diving. These divers stay in shallow waters and don’t require the use of a heavy scuba tank.
They use breathing air compressors that float on the water or are stationary on a boat. These compressors supply filtered and pressurized air to divers below via an air hose. Certain compressors can provide certain amounts of air. Some are continuous and some are timed.
We like the ones that are continuous because then you don’t have to be concerned with running out of air unless the power supply is cut off to the compressor.
Types of Diving Compressors
There are two types of hookah/snuba dive compressors which include dynamic and passive systems.
A dynamic system contains mechanical devices such as a compressor driven by a motor, which can either be electric or petrol. The system will deliver air at the correct pressure and has a holding or air reserve tank that will provide constant pressure. As the air is used and leaves the tank, more air is added to keep the pressure up. This system can be fixed or floating, and petrol or electric.
A passive system has no moving parts. It uses a compressed air reservoir such as a scuba cylinder to move air. Typically, all hookah systems are passive, but some systems used for commercial diving use a bank of cylinders on the surface as the air supply.
A fixed hookah compressor is stationary on a dock or boat while being used. If it’s floating, the air source is on a platform that the diver can take along with them.
The higher output systems utilize petrol for power. This allows one or two divers to breathe easily and dive together. Many of the commercial hookah diving systems require petrol and require more maintenance than their eco-friendly counterparts. They’re also a little louder. They’re ideal for advanced recreational diving or even commercial diving applications.
Electric-powered hookah systems are easier to maintain than petrol compressors. They can be recharged on a boat or directly connected to a power source. They’re generally very quiet to start and easy to start. Not only that, but they’re less likely to corrode. They are more suited for families and recreational use.
What to Look for in a Scuba Air Compressor
Here are several considerations to keep in mind as you begin your quest for a scuba air compressor:
- Electric or gas. If you want a more portable compressor, then gas might be the way to go. Although gas compressors are more convenient, there’s a chance of having fumes enter your tank when you use them.
- Pressure. A low-pressure compressor is adequate for diving up to fifty feet, but professional divers going over that depth should purchase a full-strength, high-pressure air compressor.
- Size of your tank. Your tank must be able to handle the pressure levels of your compressor.
- Filtration. Gas and oil-lubricated compressors require filter systems. You will often need to buy these systems separately.
- Weight. A heavier compressor will be less portable but will have more power than a light one.
- Fill time. A compressor with a fill time of 3.5 cubic feet per minute will fill an 80 cubic-feet tank in just under half an hour.
- Air quality. A compressor should put out Grade E breathing air.
Also, some compressors are noisier than others. Generators also let off a lot of heat, so the area where you will be using one needs to be adequately ventilated.
Frequently Asked Questions
How Much Does It Cost to Fill a Scuba Tank?
Most dive shops charge around $5 to fill up a tank. People don’t buy scuba air compressors to save money but to save time. Of course, some say time is money.
Can You Fill Your Own Scuba Tanks?
Yes, you can fill your own scuba tank with a special compressor specifically meant for filling these tanks. They are equipped with filtration systems, have a higher PSI rating, and are oil-less.
However, if you factor in the price of having it done at a scuba shop versus the price you will pay for the compressor, filters, maintenance, etc., the price is just about the same. On the contrary, it’s more convenient to have your own system so you’re not constantly having to go to the nearest scuba shop if you need a tank refilled.
|Brownies’||44 pounds||3+ hours||33ft||4.0 hp|
|HPDMC||18.6 pounds||Continuous||98 ft||3.5 hp|
Can I Use an Oxygen Tank for Scuba Diving?
No, oxygen tanks should not be used for scuba diving. Pure oxygen at high pressures is toxic. Scuba tanks are filled with the same air that we breathe, which has around 20% oxygen. Helium is added to scuba tanks when divers go to extreme depths. This is to decrease dangers from nitrogen.
Can You Make A Dive Compressor?
If you have the supplies and the time, you can certainly make your own hookah or snuba diving air compressor. You will need the following:
- Second stage regulator
- Connectors and fittings
- Air-breathing hose
- Water separation and particle filter
- Electric “oil-free” compressor
We recommend the following as well:
- Don’t buy a cheap regulator
- Avoid galvanic corrosion with material selection
- Don’t use a standard compressor air hose for breathing
- Avoid cheap air particle and water separation filters
We suggest the Cressi Octopus XS second stage regulator as it works at a lower 50-70 PSI, comes with 3 feet of hose and is reasonably priced.
You will also need to purchase an oil-free air compressor fitted with NPT hi-flow quick disconnect.
The air filter and water separation filter will be attached to the compressor and then the air hose assembly is attached to the filter. The compressor should then be set to 70 PSI. For complete instructions, check out this YouTube video.
We hope that you’re now able to distinguish scuba diving from hookah/snuba diving. These are two very different styles of diving with different breathing requirements.
If you’re more of a recreational underwater explorer or somebody who fixes equipment in shallow waters, then we suggest using hookah gear. On the other hand, if you’re more for deep-sea diving and underwater hunting, we suggest using scuba gear and tank filling compressors.