I’m not much of a wreck diver, and my experience is quite limited. Nevertheless, a recent article in the PADI publication The Undersea Journal caught my attention.

The article is about wreck diving, and an insert gives what author Ty Sawyer calls “15 hot wreck diving destinations.” I thought I’d share them here with you, in case you are looking for travel inspiration:

• Truk Lagoon, Chuuk
• Scapa Flow, Scotland, United Kingdom
• Great Lakes, USA / Canada
• Iron Bottom Sound, Solomon Islands
• Espirito Santo, Vanuatu
• Kwajalein Atoll
• South Florida and Florida Keys, USA
• Palawan / Coron / Cebu region, Philippines
• Bermuda
• Bikini Atoll
• Grenada, Lesser Antilles
• Vancouver Island, Canada
• Labuan, Malaysia
• United States Virgin Islands
• North Carolina, USA

I like this list for its variety—it has something for everyone, no matter where you live.

The article highlights a few noteworthy wrecks. These are the SS Yongala in Queensland, Australia, the Fujikawa Maru in Truk Lagoon, Chuuk, the SS President Coolidge in Vanuatu, the Antilla in Aruba, The Zenobia in Cyprus, and the USS Saratoga in Bikini Atoll, Marshall Islands.

Check out the article for a longer list of “other wrecks not to miss.”

Photo by Misserion

Snorkels are considered a core piece of scuba gear. Mask, fins, and snorkel: the three items every beginner starts with. We take this for granted, and dive away with those plastic tubes strapped to our head. After a while, though, we start to question the utility of a snorkel. When diving the smooth Caribbean waters, for example, is a snorkel really necessary?

At this juncture, there are a few paths the blossoming diver can take:

• Keep the snorkel. Your first option is to heed your training and continue to dive while wearing a snorkel at all times. Sure, it can be uncomfortable in a current, but you rest easy knowing it’s always there.
• Exchange the snorkel for a pocket snorkel. Your next option is to remove the snorkel from your mask. Aaah, how liberating! There are times when you may need a snorkel, so for those situations you carry a foldable pocket snorkel in your BCD pocket. In an emergency, it’s only a zipper away.
• Ditch the snorkel. Look out, divers, this future tech diver means business! The last option is to ditch the snorkel completely. I don’t imagine anyone throws their snorkel away, but rather keeps it in their gear bag and wears it on a case-by-case basis. Choppy waters with low viz? Bring the snorkel. Bonaire shore dive? No thanks.

If you find a snorkel uncomfortable, I think carrying a pocket snorkel is your best option. I don’t own one (yet), so I wear a snorkel based on the dive conditions. However, be aware that some dive operators may not let you in the water if you don’t have a snorkel. For this reason, you should always carry a snorkel with your gear.

What do you think? Are snorkels for sissies, or would only a fool go in the water without one?

Photo by chrisada

We have a quick tip today about cleaning O-rings.

It can be very easy for dirt and lint to hide on O-rings. The grease practically acts as a magnet, letting dirt easily stick. If you’re not careful, a few well-placed pieces could even compromise the seal on your equipment—a costly oversight.

To minimize these chances, try cleaning your O-rings on a white (or light-colored) surface. The white will contrast with (most) dirt, making it easier to identify and remove.

Click to enlarge
This picture shows the same O-ring, with lint, on a white surface and a wooden tabletop. While difficult to see on either, the dirty is slightly more visible with the white background. This tabletop is fairly light, so the problem gets even worse with darker surfaces.

The other day we talked about cycling wetsuits to give new life to old wetsuits. I briefly mentioned throwing out those super-old wetsuits when they get replaced by old wetsuits.

I was thinking about it, and maybe you don’t have to throw them out after all. Here are three ideas to consider before throwing it away:

• “Recycle it.” Before throwing it away, consider donating it for recycling. This can be something like Rip Curl’s Project Resurrection, where old neoprene is recycled, or something like A Warm Current (website currently down), who take old gear for kids.
• Use it for patches. While a few key areas may be worn out or torn, much of the old wetsuit probably has usable neoprene. Keep the suit around and cut it up for use as a patch when necessary. We’ll cover patching wetsuits in a future article.
• Make something out of it. A lot of things are made out of neoprene. For the artistically inclined, cut up the old wetsuit and make yourself something like a cellphone, iPod, or even a laptop case. Get creative!

I think at least one of these ideas should appeal to everyone. There’s no point dumping neoprene in a landfill, especially when it could have new life in several different ways.

The day will come. Your brand new, off-the-rack wetsuit will one day just not keep you that warm anymore. It’s time to buy a new one. Don’t feel bad, you got a good 4-5 years of diving out of it; the investment has been well worth it. Besides, a new wetsuit won’t set you back that much.

Just one thing remains: what do you do with the old wetsuit? Structurally it’s still in decent shape, so it’s a shame to throw it away. The good news is there’s a reason to hold on to it. Keep the old wetsuit, and use it for situations where it’s warm and the poor insulation won’t make a difference. Things like training in a chlorinated pool or shore diving in very warm water are perfect.

There are two benefits from keeping an old wetsuit in the closet:

1. It extends the life of your new wetsuit. By not using your new wetsuit in the pool, you save it from some harsh chemicals that will age it faster. Ditto for the wear and tear that comes any time you wear a wetsuit.
2. It extends the life of your old wetsuit. Finding new uses for old things makes you feel good. You’re keeping your neoprene knickers out of a landfill just a little bit longer.

Eventually it will get so old that it’s not even appropriate for a swimming pool. By this point you should’ve gotten a long life out of the wetsuit, so you can throw it away with peace of mind. You may even be due for yet another new wetsuit, so you can continue this cycle indefinitely.

There are many factors to consider when purchasing a snorkel: shape, mouthpiece, barrel type, valves, and even how well you like the look of it. One factor you may not consider is the length of the snorkel.

Some people might think a longer snorkel is always better. The longer it is, the less chance water will get in, right? While true, there are two other important considerations:

• Dead air space is a concept that comes up in many different areas of scuba. Dead air is the gas in airways left from the end of your last exhale. It consists of carbon dioxide, and is blocking the path for fresh air. This gas has to be inhaled first before new air can reach you, yet it is “dead” and thus worthless to your body. The space refers to where this dead air resides.

  For snorkels, the longer they are, the more dead air space they have. When you exhale through a snorkel, the carbon dioxide is trapped in the barrel. On your next inhale, you must first inhale all the carbon dioxide from the barrel before fresh air reaches your lungs. The longer the barrel, the more difficult it is to breath.

• Clearing gets harder with longer snorkels as well. When water gets trapped in the barrel you must clear it by forcefully blowing out any trapped water. Longer snorkels simply hold more water. Snorkels do have valves on the mouthpiece to force water out, but it will still take a little more effort for longer barrels.

These factors should figure in your purchase of a snorkel. Usually, a snorkel just long enough to clear the top of you head should suffice. These days they even have guards on the end of snorkels to prevent water getting in the top. You’ll pay extra for it, so it’s something to consider if you think you’ll often be snorkeling in choppy waters. Otherwise, you use a snorkel rarely enough to be worth the added expense.

Most divers never give much thought to what their air cylinder is made of. Even so, it can affect aspects of your dive. Besides, it never hurts to know a little about the equipment you’re diving with.

Material

Cylinders are made out of two types of material: steel and aluminum (actually an aluminum alloy). Each have different properties that make it appealing for different types of construction and use.

Steel cylinders are tough, making them resistant to damage. They also tend to support higher capacities, because of their increased strength. The downside to steel is that it can rust if not properly cared for.

Aluminum cylinders are softer than steel, so they’re not as tough, although they do just fine for general use. To compensate, the walls of aluminum cylinders are thicker than for steel. For this reason, an aluminum cylinder is larger and heavier than a similar capacity steel cylinder. They also don’t handle overfilling nearly as well.

Despite this, aluminum is the dominate choice of material for cylinders in many parts of the world. The upside is that aluminum tanks are far more tolerant of corrosion from salt water. As opposed to steel cylinders, when a layer of aluminum oxide, or “rust”, forms, it acts as a barrier to prevent further oxidation. 80 cubic feet aluminum cylinders are probably the most common type encountered in tropical dive destinations.

Identification

Unless you’re into metalworking, it can be hard to distinguish between steel and aluminum tanks. It’s even worse when the cylinders are painted for enriched air diving. Fortunately, manufacturers in North America are required to stamp certain information on tanks they produce, including the type of material used.

You can find this stamp at the top, rounded part of the cylinder. It is a sequence of letters and numbers stamped into the metal, arranged into two rows.

To determine the type of metal, look in the middle of the first row. These days, you will most likely see either “3AA” or “3AL”. “3AA” is the markings for chrome-molybdenum steel, which is practically all steel cylinders made today. “3AL” is the designation for the aluminum alloy used in cylinder manufacturing.

Buoyancy

The type of cylinder you use only has one major effect on your diving: your buoyancy. Aluminum tanks are more buoyant than steel, and thus you will require more weight when diving with them. It is worth knowing what you usually dive with in order to compensate one way or the other when diving with a different cylinder.

The usual recommendation is to add about 5 lbs / 2 kg to your base weighting you get from a weighting guide to compensate for an aluminum cylinder.

Aluminum has a particularly annoying characteristic. A full steel tank is negatively buoyant. An empty steel tank is also negatively buoyant, but less so. This is why during a proper buoyancy check it is recommended to use a near-empty cylinder, or add weight to compensate. Aluminum cylinders also become more buoyant as air is consumed, but they change from being negatively buoyant to positively buoyant. This means a full aluminum cylinder will sink while an empty will float. This makes it harder to pin down a perfect weighting for the entire length of a dive.

If you’re curious, a standard steel cylinder weights about 30 lbs, while an aluminum tank weighs about 35 lbs. If aluminum tanks are heavier, then how can they be more buoyant? For the same reason they’re not as strong as steel: aluminum is less dense than steel, and thus has a lower specific weight.

I hope you learned something about cylinders today. Next time you go diving, take a quick second to identify what type of cylinder you’re using. Use this information to adjust your weighting, instead of defaulting to being overweighted. Keeping note of the tank type (when different than what you usually use) in your log book could also be useful.

Scuba dive for any length of time and you’ll start wanting your own equipment. A natural follow-up question then is, “What equipment do I buy?” Let’s look through all the equipment a diver needs, which you should buy, and in what order.

Your own mask is usually high up on the list of equipment to own. This could be for a few reasons. Having a properly-fitted mask increases the comfort of your dives. Masks are one of the more “personal” items you own, so having your own that you are comfortable with is an advantage. They also are small and easy to travel with. Factor in the price on top of that, and a mask is one of the first things you should own.

Snorkels are almost always bought in conjunction with a mask, so all the previous applies.

Fins complete the trio of a beginner’s set: mask, snorkel, and fins. Some shops even require that you own each of these before beginning your open water certification. These three items also double as snorkeling gear, so their uses extend beyond scuba diving.

I was debating where to put wetsuits. In my opinion, I would rather have my own wetsuit than my own pair of fins. So why did I put it after? Buying a wetsuit is not so easy, since you feel like you are committing to a single diving locale by having to choose one thickness of wetsuit. Having to make this decision early in your diving career can be confusing. Thus, I say buy your mask / snorkel / fins set and use it for a while, then when you have a good idea where you’ll do most your diving, purchase a wetsuit (follow our wetsuit guide for help).

Having said that, owning your own wetsuit is wonderful. I personally love knowing that I’m the only person that’s peed in mine. Add a hooded vest for additional comfort and versatility.

Now we’re getting into serious diving. A BCD is not a purchase for the casual diver. They are often bought by those beginning divemaster training, or people who have been scuba diving for years and are finally tired of paying BCD rental costs.

When buying a BCD, you don’t need anything expensive or flashy (unless that’s your thing). Make sure it has enough lift and fits you well, and you can get out with your wallet intact.

Regulators often go hand-in-hand with BCDs. This time, things can get pricey. Go with a solid regulator, even if it costs a little more. Remember, you’re gonna be breathing off this thing under 90 feet of water.

I’m lumping pressure gauges, depth gauges, and octopuses into this category, since you will usually buy them with the regulator.

Weights are boring, but required gear. Don’t bother buying them unless you often go diving locally without a shop. Traveling with them is unnecessary, since you can find weights anywhere.

Ditto for a cylinder. If you’re in the market for one, you already know it. Otherwise, be glad you can get away with renting one.

This is all the required gear for scuba diving. Naturally there is other equipment, like computers, that comes up, but does not fit into this guide.

One last thing, buying gear is a big decision, but it’s not life-changing. There are a lot of choices, so don’t get too bogged down out there. Some people prefer to buy inexpensive gear as a beginner, and then upgrade later. The life on most of this equipment is in the 4-5 year range, so keep some perspective when making your purchase.

What are your thoughts? Would you recommend buying gear in a different order? Make your opinion heard in the comments.