A good and properly maintained diving cylinder, scuba tank or compressed air cylinder is one of the keys to the success of every successful dive, because breathing air in sufficient quantity and of clean quality is essential for your health when diving.
Diving cylinder made of steel or aluminum?
This is often the first question that new divers ask when they buy their first diving equipment, but the choice of the material of the scuba tank is actually not the most important issue.
In Germany and in large parts of Europe, solid steel tanks are mainly used, as they are externally more robust, always have negative buoyancy and, due to the denser material and therefore thinner walls, have a greater capacity. Disadvantages of steel bottles are their heavier weight and the fact that they can rust if used improperly.
Aluminum scuba tanks are often used for dives in salt water because they are less sensitive to corrosion. That and the lower weight are definitely among the advantages of aluminum diving cylinders. However, the material itself is not as robust as steel. In addition, aluminum compressed air cylinders have a smaller capacity as the tanks shell needs to be thicker to withstand high pressure, and aluminum tanks get positive buoyancy at the end of the dive as the fill level drops.
Regular maintenance is essential for scuba tanks
Because the exhausting continuous use in water and at high pressure demands a lot from the scuba cylinders, regular testing is vital. Therefore, in Germany, all scuba tanks need to be tested by the Technical Control Board TÜV every two and a half years, and require a yearly visual inspection in order to detect and eliminate any signs of material fatigue, rust or other defects as early as possible. Therefore, NEVER fill an untested tank with compressed air under high pressure, as the smallest defect can turn into a catastrophy at a filling pressure of over 200 bar.
What size of diving cylinder do you need?
Whether you need a 10l diving cylinder, a 12l diving tank or a 15l scuba tank – this choice depends first of all on your air consumption. The more air you use while diving, the bigger your tank should be. But if you are using a 15l tank which lasts for no longer than 45min, you should also consider analyzing other factors that could cause your high air consumption, such as a possible lack of your regulator or BCD, potential health reasons that could affect your breathing, a too high stress level which you could eventually reduce by more training and counseling from a diving professional or maybe too heavy or ill-fitting equipment or too much lead, which can also affect your air consumption. Because, even if it is nice to know that you have a lot of breathing air available when diving, you have to keep in mind that the larger your scuba tank, the more weight you carry around with you, which makes diving more difficult and stresses your back.
Diving cylinder with single valve or double valve?
This question is quite easy to answer - if you are diving with a classic regulator in quite warm waters, a dive cylinder with a mono valve, a single valve, is sufficient. However, if you also like to dive in cold water, it is advisable to use a so-called cold water configuration, meaning a regulator set consisting of two 1st stages with one second stage on each, so one powerful and unrestricted cold water-compatible first stage with the primary second stage from which you breathe, inflator hose and pressure gauge on it, and a second, possibly slightly smaller first stage to which you attach the octopus and maybe a second pressure gauge. If you use such a cold water regulator configuration when diving in cold water, for example winter diving, mountain lake diving, deep diving or ice diving, you definitely need a diving tank with a double valve.
But if you already have a dive tank with a mono valve and want to change your diving habits and plan to dive with a double regulator, this is no problem at all, because the valve on your dive cylinder can be changed at any time. Matching mono valves, double valves and also secondary valves for diving bottles can also be found in our online diving shop.
Can you also have Nitrox in your air cylinder?
Quite simply - NO! Not in Germany and in most parts of Europe! This means that you cannot simply fill your diving cylinder alternately with compressed air or nitrox at your own discretion. If you want to use breathing gas with an oxygen content higher than 21.1% in Germany and most other countries, you have to use a special Nitrox tank that has to be oxygen-free and specially labeled. You can also find Nitrox diving cylinders in our online diving shop on request.
Accessories for your diving cylinder
With a good tank and a suitable valve, you already have good basic equipment. But your scuba tank needs a little more, such as a tank boot so that you can put it down safely, possibly a carrying handle to be able to transport it comfortably or a protective net to not only protect the area in which it is placed but also the dive tank itself. You can find all these accessories for diving cylinders in a large selection and good quality here, in our online shop for diving equipment.