Before the end of 2011, the Professional Association of Diving Instructors - PADI - expects to confirm their 20 millionth scuba certification. That's a huge number of divers actively enjoying the sport of recreational diving worldwide but have you ever wondered what separates a good diver from a bad diver ? With more than twenty years experience in the diving industry, I would like to share some of scuba's good habits, some bad habits and a few of the ugly ones.

Scuba Diving Good Habits

• Every Dive is an Underwater Cleanup

There are numerous beach and underwater cleanups organized around the world each year to help remove waste products and garbage from our aquatic environments. Of course we fully endorse these activities which are usually conducted by divers, snorkelers and non-diving volunteers. The point that I would like to make about this good diving habit is that divers shouldn't need an excuse to collect rubbish from our oceans. I have personally conducted thousands of guided dives for certified divers and it constantly amazes me why they don't bring items of litter back to the boat or shore on every dive. If you spend up to an hour each dive wandering around the reefs in my local dive sites, there is enough bottles, cans, plastic and other rubbish to make a small mountain on dry land. Underwater pollution is a major contributing threat to our marine life so please join me in one of my favourite good diving habits and make every opportunity an Underwater Cleanup and support Project AWARE.

• Make Regular Buoyancy Checks and Dive Correctly Weighted

One of the common misjudgments I see regularly made by most new divers, and some experienced ones, is being incorrectly weighted for the dive. Factors that influence the amount of weight required for neutral buoyancy include the type of scuba equipment being used, water salinity content, comfort level and more, but there is a simple weight check skill that offers a true guide. A good scuba habit is to perform this weight check regularly and especially when you dive somewhere new or after a period of inactivity from diving. When a diver is correctly weighted for neutral buoyancy, the increased underwater control and comfort has numerous benefits which include conserving energy & air consumption, allowing great underwater photography, offering an enjoyable relaxed diving experience and making an unrestricted safety stop before exiting the water.

Scuba Diving Bad Habits

• Smoking and Diving

Although I may risk alienating most of my fellow diving professionals, if we're discussing bad habits within the scuba industry, one of the worst in my opinion is smoking. Smoking and Diving is hypocritical at best and dangerous at its worst. I could write reams of reasons that smoking immediately before and/or immediately after a dive is a bad habit but I think it's appropriate enough to comment that if our 'Role Model Scuba Instructors' choose to smoke during their diving instruction then what chance do we have of decreasing the number of smokers who risk injury from this habitual combination.

• Wearing your Mask on the Forehead

Most divers are aware that wearing your scuba mask on your forehead is a recognized sign of a diver in distress. That's probably a strong enough reason for most not to do so unless they actually 'are' in distress. However, from personal experience, I think the best reason not to get into this particular diving bad habit is that it's very easy to lose your mask while chatting away swimming back to the boat or shore. The mask can easily slip off the back of your head and you would be unlikely to notice it until it's too late.

• Walking around in Diving Fins

Yes it's a bad habit and it's also dangerous especially if you walk around while wearing dive fins and the rest of your scuba unit. It's very difficult to walk with fins on your feet so try to avoid this at all times. Don your fins as close to the water as possible and if you must walk with them on ...... walk backwards.

Scuba Diving Ugly Habits

• Underwater Bicycle Kicks

It's ugly to see and even more importantly it's an ineffective way to dive. You must have seen some divers riding the 'imaginary underwater bicycle'? The best way to get power from your fin stroke is to use fairly straight legs with slightly pointed fins and then use the strong powerful thigh and leg muscles in a gentle up-and-down movement. Bicycle kicking divers use an enormous amount of energy and struggle to propel themselves both under water and at the surface. Let's smarten up this ugly diving habit and take the PADI Peak Performance Buoyancy Specialty.

• Spitting into the Mask

It's not pretty to witness divers using saliva to stop their mask fogging underwater and I've always thought it was unhygienic. For many years I have used a cheaper alternative to the commercial anti fogging solutions. Baby shampoo has little or no chemicals in it and works really well if you apply a thin layer to the inside of your mask with a quick rinse before you enter the water.