Welcome to Total Bottom Time!

Total Bottom Time is my online personal dive log. A place where I can share my dives with friends, family, other divers, and the world. You can find out a bit more about me and see my full log of dives by clicking on my profile on the right. Feel free to subscribe to my dives via email or RSS.

Below are just some of my latest dives.

The third and final training dive of the Self-Reliant Diver Course was essentially a dive planned and led by me. I choose the dive profile and the route taken then led the dive as if I were solo. I chose a max depth of 10 metres and a max time of 35 minutes with a turn around time limit of 17.5 minutes or 133 bar, whichever came first. That profile didn't require as much air as the second dive of the course so I only had to bring the little 2.7 litre pony bottle with me.

But the third dive still had a number of objectives:

1. Write the depth and time on a slate at 20 bar intervals
2. Turn around at a predetermined time limit or air pressure limit
3. Navigate the entire dive without assistance
4. Switch to the redundant air supply
5. Deploy a surface marker buoy (SMB) on reel with a line while breathing off of the redundant air supply
6. Do all of the above within the planned dive profile 

I used the same slate as the second dive to write the depth and time since the slate has multiple "pages".

Navigation was a combination of compass ...

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The second training dive of the Self-Reliant Diver Course involved some planning. The main item to plan was how much air would be necessary for the dive using the surface air consumption (SAC) rate determined on the first dive of the course, which was 20 litres/minute.

Here are the formulas:

Air required = SAC * ((depth + 10 metres) / 10) * time * 1.5 reserve

Cylinder size in litres = air required / maximum pressure

For the second dive we planned for a max depth of 12 metres for 50 minutes and here's how the formulas worked out.

Air required = 20 * ((12 + 10) / 10) * 50 * 1.5 = 3300 litres

Cylinder size = 3300 / 200 = 16.5 litre cylinder

I was using an 11 litre cylinder main tank, which meant I need an extra 5.5 litre cylinder. However, the pony bottle I used on the first dive was only a 2.7 litre cylinder. That meant I need a larger cylinder as my redundant air supply and the only larger cylinders available were the 11 litre cylinders.

So I went on the dive with one 11 litre cylinder on my back and one 11 litre cylinder in front of me clipped to the left-hand side ...

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I decided to take the PADI Self-Reliant Dive course. Learning how to be a self-reliant diver teaches a good set of skills for any diver. But, of course, the real goal is solo diving safely.

What's my motivation for solo diving? It's simple, I want to dive at my own pace.

Buddy diving is great but inevitably I want to stop during a dive and hang out in one spot to take photos and videos. Far too often I look up and my buddy or group have continued to cruise along and are almost beyond visibility. I have to hustle to catch up, quickly bypassing even more interesting sites.

Hence, I'm taking these first steps towards being a self-reliant diver and solo diving.

The course began with some classroom training and a knowledge assessment. This covered a lot of good stuff like self-rescue, self-reliant skills/mentality, equipment redundancy, planning, and self-management of dive emergencies. It was a mix of fundamentals, calculations, and common sense.

The course also requires three training dives. The biggest change for me is the addition of a pony bottle to my gear. The pony bottle is a redundant and independent air supply. It ...

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