ski&dive
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Every time you go to a dive resort, you are asked "How much weight do you need?" Usually divers reply with the amount of weight they used on their last trip, if the remember. Otherwise it is a "duh?" conversation.
If you remember your original open water diver training, the amount of weight you need depends on your wetsuit and whether it is fresh or salt water and of course your anatomy. Your instructor probably looked at you and said here is 16 lbs of weight. You were probably overweighted but didn't know it. It is easier for an instructor to deal with an overweighted student than an underweighted or properly weighted student. And after you got certified, you probably used the same amount of weight until someone told you were overweighted.
I have been diving for a long time. Many years ago I had a divemaster who had an issue with overweighted divers and challenged everyone to see how much weight we could drop. I don't remember how much I took off by the end of the week but now I usually use 8-10 lbs with a 5/3 wetsuit. But in warmer water I dive in a thinner wetsuit or even a Lyra skin and to my surprise I still need the same amount of weight. That is unless it is a new wetsuit. I recently purchased a 3/2 Body Glove suit and the 10 lbs was barely enough. But by the end of the week, after 20 dives the wetsuit compressed and I probably could have used only 8 lbs. It's my belief that after a wetsuit is "broken in," it offers little additional buoyancy, regardless of the original thickness.
But there are other things to consider when answering the question about how much weight you need. One is current. If there are strong or even moderate up and down currents, you will probably want to take a couple of pounds more weight, especially if you dive with no air in your BC. Also you may want more weight if the dive plan is for a "negative entry" where, because of currents, you jump off the boat and immediately descend to the reef.
On a recent trip, another factor came into play. It was the weight of the tank. You may have been taught about the different tanks. Most of the places we have been use 80cf Aluminum tanks. But on occasion we have been to places using 72 cf AL tanks or 72 cf Steel tanks and one time a fat steel tank. Unless you can see the specs for the different tanks, you basically guess what adjustments you will need to make. I've found that in these cases, it is probably better to be overweighted for the first dive and take out weight before the second dive. On a recent trip to the Maldives and we were told the tanks were "heavy" "American" tanks. They were Catalina 3AL 228s. They looked like the same tanks we always use and the tank straps did not need any adjustment. Based on that we took 4 kgs (8.8 lbs) for our first dive. I was a little heavy and dropped it to 3 kgs for later dives. After the week of diving with the 228s, we went on a liveaboard the next week. These were also Catalina 80 cf AL tanks but after looking at the stamps, they were Catalina 3AL 207s. I went back to my usual 10 lbs and was properly weighted. Again, the size of the tank seemed the same as the 228s but they were obviously lighter. When we got back, we checked the specs for the tanks and found there was about a 4 lb difference in weight.
Another factor that effects our weights is the salinity of the water. In fresh water, I need little to no weight. In salt water, I need usually need 10 lbs. But if the salinity is lower either because of the general salinity of the area or fresh water runoff, I need only 8 lbs. Not much of a difference, but again, it you dive with no air in your BC, it is noticeable.
And finally, what are you carrying? I used to have a Nikonos V with a strobe that was the equivalent of carrying an extra 2-3 lbs of weight. Now I use a Canon G9 and the big housing is about a pound positive. A floaty light can also increase the weight you need.
And don't always believe the numbers stamped on the weights. Unless they are commercially produced weights, they may vary considerably from the weight stamped on them. We have also been told the weights were in kilos when actually they were in pounds, about a 10% difference.
How much weight do you need? It not really a simple question.
If you remember your original open water diver training, the amount of weight you need depends on your wetsuit and whether it is fresh or salt water and of course your anatomy. Your instructor probably looked at you and said here is 16 lbs of weight. You were probably overweighted but didn't know it. It is easier for an instructor to deal with an overweighted student than an underweighted or properly weighted student. And after you got certified, you probably used the same amount of weight until someone told you were overweighted.
I have been diving for a long time. Many years ago I had a divemaster who had an issue with overweighted divers and challenged everyone to see how much weight we could drop. I don't remember how much I took off by the end of the week but now I usually use 8-10 lbs with a 5/3 wetsuit. But in warmer water I dive in a thinner wetsuit or even a Lyra skin and to my surprise I still need the same amount of weight. That is unless it is a new wetsuit. I recently purchased a 3/2 Body Glove suit and the 10 lbs was barely enough. But by the end of the week, after 20 dives the wetsuit compressed and I probably could have used only 8 lbs. It's my belief that after a wetsuit is "broken in," it offers little additional buoyancy, regardless of the original thickness.
But there are other things to consider when answering the question about how much weight you need. One is current. If there are strong or even moderate up and down currents, you will probably want to take a couple of pounds more weight, especially if you dive with no air in your BC. Also you may want more weight if the dive plan is for a "negative entry" where, because of currents, you jump off the boat and immediately descend to the reef.
On a recent trip, another factor came into play. It was the weight of the tank. You may have been taught about the different tanks. Most of the places we have been use 80cf Aluminum tanks. But on occasion we have been to places using 72 cf AL tanks or 72 cf Steel tanks and one time a fat steel tank. Unless you can see the specs for the different tanks, you basically guess what adjustments you will need to make. I've found that in these cases, it is probably better to be overweighted for the first dive and take out weight before the second dive. On a recent trip to the Maldives and we were told the tanks were "heavy" "American" tanks. They were Catalina 3AL 228s. They looked like the same tanks we always use and the tank straps did not need any adjustment. Based on that we took 4 kgs (8.8 lbs) for our first dive. I was a little heavy and dropped it to 3 kgs for later dives. After the week of diving with the 228s, we went on a liveaboard the next week. These were also Catalina 80 cf AL tanks but after looking at the stamps, they were Catalina 3AL 207s. I went back to my usual 10 lbs and was properly weighted. Again, the size of the tank seemed the same as the 228s but they were obviously lighter. When we got back, we checked the specs for the tanks and found there was about a 4 lb difference in weight.
Another factor that effects our weights is the salinity of the water. In fresh water, I need little to no weight. In salt water, I need usually need 10 lbs. But if the salinity is lower either because of the general salinity of the area or fresh water runoff, I need only 8 lbs. Not much of a difference, but again, it you dive with no air in your BC, it is noticeable.
And finally, what are you carrying? I used to have a Nikonos V with a strobe that was the equivalent of carrying an extra 2-3 lbs of weight. Now I use a Canon G9 and the big housing is about a pound positive. A floaty light can also increase the weight you need.
And don't always believe the numbers stamped on the weights. Unless they are commercially produced weights, they may vary considerably from the weight stamped on them. We have also been told the weights were in kilos when actually they were in pounds, about a 10% difference.
How much weight do you need? It not really a simple question.
