Oceanic Jetpack BCD Review

The Oceanic Jetpack BCD is a bit of an anomaly, it is a one size fits all travel BCD that strives to slim down all of our favorite aspects of back inflate BCD’s into one convenient package.  The Jetpack BCD comes in two different packages one thats just the BCD and the complete package which includes a detachable backpack.  The gimmick of the Jetpack is that this BCD transforms from a bag able to fit all of your personal gear, to a light weight travel style bcd with a large amount of personal adjustment.

In terms of what this bcd is designed for it does function well, everything about it makes sense and performs the way it should.  With that being said i’m just not in love with this bcd.  I am a fan of all of the features, many of them are clever and makes sense in their purpose, but it just doesn’t feel the way I want a travel bcd to feel.  Lets start by covering the features of this bcd.  The Jetpack is designed as a travel bcd, but not the traditional travel bcd.  Instead of purely going for the most light weight and basic design to cut weight for checked baggage, the Jetpack does cut weight but doesn’t cut as much retaining some of the many comforts of a standard bcd.

The breakdown/set up

jetpack diagramThe jet pack is made as a one size fits all bcd that almost completely comes apart, removing the cumber bun weight pockets and storing them in the zip away rear panel that contains the bladder, inflator, tank straps, cumber bun and weight pockets when in the travel mode.  In this configuration there is a backpack that can attach to the broken down bcd and can be used as a carry on bag for airline travel.  This system does work pretty we’ll and the detachable backpack is very large and has a great amount of storage space.  The set up is fairly simple, the rear panel unzips and rolls up secured with a few pieces of velcro the bladder extends beyond the edges, the cumber bun, weight pockets are attached and the shoulder straps are unclipped from the base of the bag and attached to the weight pockets.  The most difficult part is threading the cumber bun through the hidden loops and adjusting the shoulder straps for personal comfort lengthening and shortening the nylon webbing.  The cumber bun does attach using velcro attaching to itself appears to be surprisingly secure but I can only assume that over time the velcro will give out.  But for the time being it appears to be working just fine.

What I like:

The truth is this BCD does really work well, the modular pieces feel secure when attached and provide an abundance of adjustability.  One feature that I am very happy to be included is the  cumber bun, most travel bcd’s this is the first feature to be eliminated in order to cut weight.  For me it provides an additional level of security and makes the bcd feel like it is wrapping around me more.  They also employ a different stomach strap jetpack bcd 2system from other Oceanic BCD’s instead of the traditional pull from the center out the straps are laced back and use a pul from the sides to center, This is a feature i have seen on many Aqualung bcd’s.  The back inflation style makes it a very comfortable dive and uses high quality durable materials that dry relatively quickly.  The materials never felt over saturated with water leaving me wondering if it had dried fully before packing.  The last thing I am very fond of is the backpack, this thing is great.  Weather it is attached or detached this thing has a ton of space, pocket for laptop, many interior mesh pockets for storage of small items, two exterior pockets, straps on the sides great for sandals or beach towels, and zips completely open which can be nice when you are unpacking or looking for something in the bag.

What I don’t like:

For the most part I am pretty happy with the Jetpack, it functions how a bcd should and has many features that I wish a traditional travel bcd would have, but it is not perfect at least not for me.  I am not a tall person and the length of this bcd is a little too much, I jetpack 3feel like no matter how much i play with the adjustments that I cannot get it to sit perfectly for me because I have a short torso.  I have also found that the placement of the deflator is just not right for me I find my self having to adjust my body positioning more while diving to deflate.  This could be because of the length of the bcd and how it fits my body or just that I am so used to my primary bcd I need more time to adjust.  Another small issue I have is the weight, for a travel bcd the jetpack is a little heavy, about 6.25 lbs which is lighter than a traditional bcd but also heavier than most lightweight travel bcd’s sitting somewhere in the middle.  The salvation for this issue is that it packs into a backpack and can be used as a carry on so weight is not as much as a factor in the long run.  My final issue is with the placement of the tank strap, I understand that for the length of the bcd it has been set low to prevent swing of the tank but I wouldn’t mind an additional strap a little higher for a more secure hold, it does have a valve strap that can aid in some stability but I personally prefer a double strap system.

In the end it is going to depend on what you are looking for in a travel bcd, if you are looking for something that is very adjustable, and can be used as a carry on this is a perfect option.  If you are looking to cut as much weight as possible then it may not be the best option.  It does function as a high quality bcd with durable materials and I experienced no technical issues.  The price is a little high for a travel bcd with the Jetpack Complete (includes backpack) coming in at $599 while most travel bcd’s are around the $450 price range.  The one size fits all feature may be a bit exaggerated not the most ideal for those who are on the shorter side but as a bcd that could be an extra for a friend not needing to worry if it fits is a very nice option.  Over all I do like the Jetpack, it functions well as a bcd and has many clever features but I am not in love with it.

Diving Masks Too Many To Choose From

The Scuba diving mask is the most integral park of diving equipment and usually one of dive mask 5the first pieces of equipment a diver buys.  There are no shortage of mask to choose from with a variety of options, from skirt color, number of lenses, lens colors and strap styles.  Despite all of these variations the most important feature of any mask is fit and comfort.  The fit and comfort of a mask is a personal decision but these other options for mask style can help narrow down which masks to start with when choosing a mask.

Skirt Color:

The first and most obvious variations of a mask is the skirt colors.  All mask intended for diving use high quality silicone that is made to be durable, soft and long lasting.  With clear silicone mask they allow a lot of light into the mask providing a wide open feeling, this is a very common option for starting divers.  Some diver may notice that allowing the light into the mask may cause a visible reflection inside the mask which may be distracting.  Black or solid colored mask prevent the excess of light through the skirt of the mask, this can cause a feeling of tunnel vision which may be detrimental for those that are susceptible to claustrophobia.  Free divers, spear fishermen, and photographers tend to prefer solid colored or black silicone mask because they block this light and allow for the eyes to adjust to lower light conditions much quicker.

Number of Lenses:

The lens is a very integral part of the diving mask and provides the template for which the shape of the mask is formed.  The two most common mask lenses are either a single lens design, a dual lens design and a panoramic design.  All are effective and functional as a mask lens and provide their own positive and negative aspects.  The single lens design provides an unobstructed field of vision, allowing for a wide open feeling for the user, it also usually brings the frame of the mask lower on the bridge of the nose that for some people can cause uncomfortable contact that could become very uncomfortable.  The dual lens design generally will allow more nose space because of the separation of the lenses that can be more comfortable for some, this separation of the lenses can cause a obstruction or blind spot that can be noticeable for some divers.  The panoramic design provide peripheral windows on the side of the mask and can be paired with single and dual lens mask.  This style of mask increase the field of view for divers while also increasing the air volume inside the mask.  Some divers prefer this more because of the open  field of view.

Framed or Frameless:

Frameless mask are growing in popularity, these mask remove the plastic frame from the design and have the silicone wrapped directly around the lens.  This design is popular because it reduces the volume of the mask and potential for parts that can break.  The downside of the frameless mask is in instances of prescription lenses there are only the option to have lenses bonded into the mask.  Traditional framed mask in some styles have replaceable lenses that can be installed to accommodate standard vision correction.   Some of these mask designs can be either very high volume or low volume in design covering a very wide assortment of styles.

High or Low Volume:

In diving the volume or air space in a mask is something that has evolved since its inception where mask originally had a very high volume with large windows for a greater viewing space.   As technology has evolved the mask and the rise of popularity in free diving the low volume mask has increased in popularity.  Low volume mask require a lower amount of air and effort to clear the mask when flooded and equalize the airspace, which is very important when free diving, but not so much when diving.  Because divers have a supply of air it is ok to use more air to equalize the air space or clear the mask when flooded.  Both are suitable options for divers, but those that might be looking for a dual purpose ideal for free diving might look for a mask with a lower volume.

Lens Color:

Lens colors are options traditionally taken on by spear fishermen, using colored lenses to help the eyes adjust to low light conditions, when looking under ledges and into crevices.  The most common lens colors are clear, amber/yellow, and HD lenses.  Clear lenses are the most common and virtually all mask come with this standard option.  The amber/yellow lenses are found in spear fishing/ free diving low volume mask, these mask like yellow lenses for snow skiing help the eyes adjust to low light conditions, ideal for searching for fish in holes, crevices and under ledges.  the HD lens is a pigmented lens that is used to restore color lost with depth.  These lenses often have a mirrored appearance from the front and generally have a red or rose pigment to the lens itself.  Lens color is a less common option for most mask designs and generally are specific to higher quality mask designs.

Mask Straps:

The silicone mask strap is the most widely offered standard for diving mask, some select mask offer neoprene mask straps.  The silicone mask strap commonly offers more easily adjustable straps for quick and fine adjustments, while the neoprene mask although nicer for longer hair can be adjusted but not as easily or on the fly.  With this being said any mask can be outfitted with a neoprene strap either by replacing the entire mask strap or a cover that slides onto the mask strap.

Conclusion:

With many different considerations in choosing a mask it is important to note that the fit and comfort of the mask are the most important factors.  These additional options of silicone color, number of lenses, frameless/framed, high/low volume, lens color, and type of strap these are secondary considerations when choosing a mask, there are many mask out there and a mask to fit each face.

Scubapro Hydros BCD Review

hydros 4The Scubapro Hydros BCD is a step in a new direction in terms of what a BCD can be.  The scuba pro Hydros has been designed from the ground up using a new material to BCD’s Monoprene.  This monoprene material similar to rubber/silicone gives the bcd a grip and flexibility that is unheard of in any other BCD.  In addition to the new material the Hydros is made to be a versatile cold water and travel bcd, with removable weight pockets and a simple harness system for travel.  This is truly a unique approach to a bcd that will likely have copycats in the near future.

Features:

  • Monoprene Material
  • Travel harness
  • 12 lb quick release weight pockets X2
  • 5 lb trim pockets X2
  • Scubapro Air 2 integrated octo (BPI optional)
  • 40 lb lift bladder
  • Multiple color kits
  • Pocket accessory options
  • Carry backpack

The Material: Monoprene is a material that is not new to the diving industry, for a long time it has been used in diving fins as a durable rubber material, with plenty of flex.  This material is also very grippy, and being used in a bcd solves the problem of the shift.  The shift is a common problem divers have when at depth or at the surface when the material of the bcd does not grip to the user and shifts requiring the user to adjust and shimmy the bcd back into place.  With this new material the monoprene of the hydros sticks to the user and eliminates the possibility of the bcd shifting.  Another added benefit of the material is its lack of water retention, the only material on the bcd that may hold water is the webbing and the bladder, the bcd will usually dry out completely 15-20 min after exiting the water making it ideal for travel and packing up into a car after a dive.

All around BCD:  The hydros is a true chameleon of the bcd world made to be tough and rugged with plenty of lift and weight capacity, and capable of transforming into a lightweight bcd ideal for travel.  Now don’t get me wrong when this bcd has some weight to it, the monoprene material makes it one of the heavier bcd’s in my opinion coming in hydros 3at a almost 11 lbs with the pockets attached.  But if you are planning on traveling with the hydros it also comes with a harness system that quickly replaces the pockets with a little practice.  Now this harness system is very simple no pockets just webbing a couple D rings and clips, don’t forget you still have the trim pockets on the back of the bladder for weight integration, although it will not be quick release.  Despite that this is an easy way to cut significant weight from the bcd when traveling.  So for divers looking for a bcd that is ideal for cold water diving and travel the hydros bcd checks all the boxes.

The accessories: There are many additional features that come standard with the Hydros BCD, travel harness system, and a carry backpack large enough to fit the bcd, regulator, mask snorkel inside and a pair of the Scubapro Go fins on the outside of the bag.  While these are welcome additions to any standard bcd package i would like to discuss the additional accessory mounts for the Hydros.  The first and most notable accessory are the color kits: Blue, yellow, pink, orange, and purple  The men’s bcd comes standard with black and the women’s bcd comes standard with white.  These kits that replace the weight pocket coverings are a nice way to accessorize and personalize a bcd.  In addition

hydros accessories
Top: Color kits, Ninja Pocket, Thigh Pocket                   Bottom: Bungee mount, D-ring mount, Knife mount

to these color kits there are also attachable accessories for knife mount (specific to scubapro knifes), D-ring mount, bungee mount (large and small), ninja pocket, and thigh pocket.  I find most of these additions as cash grabs from Scubapro for not intentionally adding useful accessories.  While the look of the weight pockets are slick and clean looking there are only functional for carrying weights without additional accessories, no pockets for storage, necessary additional hardware to mount a knife, and D-ring mount is largely underwhelming.  There are 4 possible mounting locations on the weight pockets for these additional accessories, but there are no mounting options available for the travel harness for these or any accessory mounts.  My least favorite of these accessories are by far the pockets, I have never been a fan of a roll up pocket like the ninja pocket, to have something flapping by my leg when I need to store something away.  While the hidden pocket of the traditional bcd design is my least favorite pocket type, the thigh pocket has now taken the lead.  While it is secured and not flopping about to have to secure it around the leg and have it attach to the bcd using a clip makes me wonder why someone wouldn’t just have a pocket attached to their wetsuit instead.  But then again that is my personal opinion of this style of pocket.

Pros:

  • Quick drying Monoprene material
  • removable weight pockets & travel harness
  • Travel backpack
  • 40 lb lift capacity
  • Optional BPI or Air 2 alternate

Cons:

  • Accessories
  • Not to be worn without Wetsuit/ rash guard

For a bcd that starting price is $916 with standard BPI or $1049 with Air 2, it is a little frustrating that simple convenience accessories are add ons and not standard.  While personally i find many if not all of these accessories useless in my style of diving, I see where some divers could find use in them.  The knife mount I find annoying because it is only useful for proprietary use with their own brand of knife, which i understand, but also believe there should be a standard mount distance with all knife and bcd brands, but that is just a distant dream.  My other frustration comes from the pockets while the ninja pocket is not my personal ideal, it is the thigh pocket that I truly have distaste for.  To consider donning and doffing this bcd that is well known for its comfort and fit and hydros bcd 1taking an additional step to clip a pocket around my leg so it does not flap about during the dive for the sole purpose of having additional storage space seems ridiculous to me as a purchase and an optional accessory.

In conclusion the Hydros is still a high quality BCD, that with its new Monoprene material provides a comfortable, quick drying bcd that sticks to the user with no shifting, for a truly secure fit.  Although it sits at the higher end of the price spectrum for most BCD’s it proves its value with its versatility and quality.

 

Oceanic Pro Plus X Review

With the drastic strides in technology of dive computers and the growing efforts by every major brand to put out the latest and greatest Oceanic has managed for at least the moment to edge out the competition.  For years the iconic Pro Plus line has been a staple of the Oceanic brand there is no surprise that they have managed to put out a dive pro plus x 1computer that is the complete package.  The Pro Plus series has always been a favorite of many divers despite brand devotion because of the large easy to read display popular with aging divers looking to ease the stress of the traditional tiny displays of most computers.

Like many of the other newest computers on the market the Pro Plus X has all of the standard features of an air integrated console, air and nitrox compatibility, water activation mode, alarm settings for safety stop, deep stop, gas time remaining, and many more.  Standard to the Oceanic line of computers it uses a dual algorithm that can be changed between DSAT & Pelagic Z+.  For Full Specs on the Pro Plus X visit Oceanic’s website with this Link.

What Makes the Pro Plus X Special?

The Pro Plus X was one the first computer to use TFT (Thin Film Transistor) to allow for apro plus x menu vibrant full color display that is readable in direct sunlight and glare.  It is one of the first computers from oceanic to use a Lithium Ion rechargeable batteries.  Bluetooth capable and able to download directly to the diver log app with no chords.   Finally in my opinion one of the easiest and intuitive menus with 4 button navigation for complete control.  Now at this point in time it is standard for high end dive computers with full color screens to have TFT, rechargeable batteries and bluetooth capability.  In terms of air integrated console computers the Oceanic Pro Plus X is clearly a trend setter, and the beginning of a new wave of high quality dive computers for divers that want bright easy to read dive computers.

Pros:

  • Large easy to read display
  • TFT (thin film transistor) screen
  • Rechargeable battery
  • Bluetooth capability
  • 4 button navigation
  • Intuitive menue system
  • Quick disconnect on hose
  • Digital Compass

Cons:

  • Price $1449.95
  • Console design

With the current movement of the dive industry the price is not totally uncalled for it does provide a high quality product that is very easy to use and progresses the brand of pro plus x 4the Pro Plus computer.  While it is launching oceanic into the high quality dive computer the Pro Plus X is priced a little high compared to comparable computers on the current market, it would be a much better selling computer if it were priced around $1000 dollars and would be an absolutely worth while purchase at that price especially as an upgrade for the Pro Plus 3.

As technology continues to advance more and more divers are adopting a more simplified regulator and total diving system ideal for travel and cutting weight and reducing hoses when applicable.  Because this is a console mounted computer it is being left in the dust by computers like the Scubapro G2 a wireless air integrated wrist computer.  I believe if the Pro Plus X were adapted to a wireless air integrated wrist computer it would be a the computer to have.

In conclusion if you are looking for a bright bold console computer the Oceanic Pro Plus X hits the nail on the head.  Everything functions just the way it should, the menus are simple and easy to navigate, the screen is bright and legible even in direct sunlight (i keep mine at 10% brightness)  and underwater is a dream to use and get all the information I need at a quick glance.  This computer may not be for everyone largely because of the price but is still a very high quality computer worth considering if your looking to upgrade.

Zeagle Scope Mono Review

The Scope line of mask from Zeagle is their first ever release of any masks.  While Zeagle is most well known for their high quality rugged BCD’s and along with the recent release of the Zeagle Recon Fins they have broken ground into the soft gear market.

The Scope line of dive masks includes the Dual and Mono masks.  The obvious difference between the two is the number of lenses, the dual is a two lens mask while the mono is a single lens mask.  Some of the features of each mask include:

Scope Dual:Zeagle Scope Mono

  • Replaceable lenses
  • Color lens frame kit options
  • Standard silicone straps

Scope Mono:

  • Frameless mask design
  • Low volume
  • Elastic soft ski goggle style strap standard

The straps for the masks can be interchangeable using a Allen screw design similar to the Zeagle recon fin straps.

Now while I have been fortunate enough to test both mask I have much more experience with the Scope Mono Mask.  While mask are a personal fit everything said is subject to my opinion and personal experience with the mask and may be different for another person.

What I like about the Zeagle Scope Mono mask,  because of the single lens design this mask provides a very wide field of view giving the person waring it a very open feeling for a black silicone mask.  There is a very wide set nose pocket on the mask providing extra space for those with larger noses despite the single lens design, I have a moderately large nose and found only making contact from the bridge when I excessively suck air from the mask or am unable to equalize the airspace.  For those with excessively large noses i would recommend the Scope Dual.  I was skeptical of the mask strap but found it fairly easy to adjust and with the amount of stretch never felt excessively tight.

Problems I have with the Zeagle Scope mono, the first issue i noticed with the mask was that it was relatively narrow for my face.  I was still able to get the mask to seal on my face but did feel narrow at least compared to my goto mask the Oceanic Shadow.  I also found that with the Scope Mono if i had neglected to shave for a couple of days the mask would begin to leak excessively, this was a annoying problem during a dive but easy to avoid once i figured out the cause.  Another issue that was easily remedied was the attached snorkel keeper on the mask strap.  Fortunately the snorkel keeper is removable unlike some other ones on similarly designed mask straps.  I found all of these problem to be minor issues and easily dealt with.

Overall I very much enjoyed using the Zeagle Scope Mono mask, it is a comfortable low volume mask with a wide field of view that had a surprisingly comfortable strap for diving with and without a hood.  This is definitely a mask that I will be adding to my active rotation of mask.

 

Check out the Video Review on Youtube Click Here

Oceanic Omega 3 Review

OceanicOmega3
Oceanic Omega 3 2nd stage, & FDXi 1st stage

The Oceanic Omega 3 regulator paired with the new FDXi first stage is a bit of the black sheep in the current market.  The first thing many people will notice is that it is a side exhaust regulator, but it is so much more than that.  The Omega 3 is the 3rd generation of the Omega family, earlier generations the 1 and 2 are still coveted by divers and their simple design makes for easy upkeep and an assortment of customizable options.  My first experience with the omega line was a few years ago after my scuba pro second stage fell apart during a dive, in dire need of a replacement and low on funds I found an old Omega 1 at the shop I was working at.  The side exhaust was a breath of fresh air, no more bubbles all over my face when I am looking around.  The metal servo valve also allowed contestation to build which eliminated dry mouth.  So when I heard that Oceanic was preparing to release the new Omega three I began to save up.

With the Omega 3’s sleek design that brings the classic Omega shape into the 21st century.  Along with the new design Oceanic also added a pre-dive switch, and pivot to the second stage, reducing free flow that omegas were notorious for, and improving comfort for the user.

Oceanic Omega 3 2nd stage
Oceanic Omega 3

The Pros:  With the design of this regulator and the use of a servo valve instead of the standard on demand valve, the effort needed to breath is almost non-existent.  the side exhaust design reduces the sound underwater because bubbles are no longer rushing past both ears, only one ear.   This can take a little getting use to but overall it is a quick transition.  The metal servo valve allows for condensation to build inside the housing reducing dry mouth, and the issue of being a wet breather found in the 1st and 2nd generations of the Omega’s has been solved.  The pivot on the second stage makes for comfortable position of the regulator, no longer being pulled or torqued  when looking around.  The pre dive switch is a happy addition to deal with the finicky free flow of the previous generations, a quick twist of the base and you are ready to dive, easy to use wearing even the thickest gloves.  The FDXi first stage provides the simplicity and sturdiness of the FDX10 but in a smaller sleeker design.  In terms of upkeep, the simplicity of both the first and second stage make for quick turn around times during services, and require minimal parts specific to Omega 3 and FDXi.

FDXi
Oceanic FDXi

The Cons: Even though this regulator is a very easy breather, there is still a bit of adjustment that is needed to make perfect for each individual diver.  There is an adjustment port at the center of the exhaust that with a screwdriver can be adjusted to increase or decrease the inhalation effort, this can take a little bit of time to get it to your own personal setting for comfort but once it is set you don’t have to worry about it.  My only real issue with the regulator is the first stage, it works very well but the ports are placed a little to close together so in order to remove one hose you might have to remove them all.  If you use a transmitter for your computer it is very difficult to fit a crescent wrench in to secure.  My last issue with the FDXi first stage is the yoke frame, it is very broad and makes it so the first stage does not fit all tank valves which can be a little inconvenient.

Me:Omega 3
Diving in Cozumel with the Omega 3 and FDXi

Overall this is an amazing regulator, it breaths well, it is very comfortable to use and the side exhaust makes for in my opinion a much more enjoyable dive.  The Oceanic Omega 3 may not be for everyone but  I do Strongly encourage every diver to give this side exhaust regulator a chance because it may just change the way you dive.

Unfortunately through industry connections I have been informed that the Omega 3 has been discontinued, because of diver complaints of it being a wet breather and finicky.  These characteristics that divers complained about were staples of the Omega design and what made it so unique.  Although this may not be ideal for all divers for some these qualities can be seen as an advantage along with its ambidextrous nature, and welcome the out of the box innovation that the Omega and all generations have incurred.  As a diver I will sorely miss this marvel of design and am sorry that other divers misunderstanding of this piece of equipment will call for its discontinuation of production.

Oceanic Omega 3 video review.

Tank You for Asking

IMG_0217
Blue Tanks are LP Steel 72’s, Yellow tanks are AL 80’s 50’s & 65’s

Scuba tanks while a very important piece of equipment are often under appreciated.  While many divers are taught about tanks in their open water certification the role of a tank is left as the container of air.  But in many cases the choice of tank can be as important as choice of BCD or fins.  For most divers tanks are something that they might not normally think about, you travel to your destination and the shop provides tanks for you.  Some divers might be surprised to find out that there is as much variety in tanks as most other pieces of scuba equipment.

IMG_0213
Aluminum Tanks, AL50, AL65, AL70, AL 80

Many divers are unaware of the effects of tank choice has on our diving especially buoyancy and time.  Tanks come in a variety of sizes, the size of the take is determined by the volume of air that it is able to hold.  A common tank size is 80 cubic feet, but these sizes can vary from as small as 6 cubic feet for a backup pony bottle to as large as 149 cubic foot high pressure tank.  It is pretty obvious that the larger tanks will hold more air than the smaller if they are filled to the same pressure, but with the use of different metals and high and low pressure tanks this can also vary.  For the most part Aluminum tanks despite the size will be filled to 3000psi, steel tanks on the other hand have a fair amount of variance.  Low pressure steel tanks are exactly what they sound like they are rated for a lower pressure, depending on the tank it can range from 1800psi to 2600psi.  High pressure tanks (commonly using a DIN valve) fill on average to 3445psi, which is higher than the standard 3000psi of aluminum tanks.  What this means is that tanks that fill to higher pressure have more air packed into them than tanks that are the same size that till to a lower pressure.  So by choosing tanks that are larger and fill to a higher pressure (my favorite is HP80) you can increase your dive time compared to a smaller tank.

IMG_0215
High Pressure tanks with DIN valves, left to right HP 65 (with Yoke Insert), HP 80, HP 100

While size of tank might be an obvious way to increase dive time, tanks also greatly influence our buoyancy underwater.  With different choices of metal aluminum being a weaker metal and steel being a stronger metal these weights contribute to our buoyancy underwater.  Although aluminum is a lighter metal because it is weaker the walls of the tanks are much thicker.  This does usually give tanks a greater overall weight when full, when the tank is emptied the is a drastic swing in its buoyancy characteristics.  Aluminum tanks while they may vary slightly from manufacturer generally are about 4 lbs positively buoyant when empty or near empty.  This means you will be lighter at the end of the dive making it more difficult to complete a safety stop.  On the other hand while steel tanks are a stronger metal they don’t require as thick of walls and on average may be 1 lb positively buoyant to 2 lbs negatively buoyant depending on the manufacturer.  This means with a steel tank that might be 3 to 4 pounds less lead you will have to add to your weights.  The high pressure steel tanks can even be up to 4 lbs negatively buoyant when empty.

So weather or not you are buying a tank or renting a tank it is important to know how it is going to affect your dive, weather its is going to affect the duration or your buoyancy.  Be prepared to make adjustments as necessary.  If your unsure talk to the dive professionals to find out the buoyancy characteristics, and don’t forget to record in your logbook, your weights with each type of tank you use so you never have to second guess again.