Weighty question...
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If you will be diving the same gear as you do in salt water you subtract weight based on your body weight. According to PPB literature you subtract weight going from salt to fresh water based on your weight as follows: 100 - 125 remove 4 lbs., 126 - 155 remove 5 lbs, 156 - 186 remove 6 lbs, 187 - 217 remove 7 lbs. This is just a recommendation doinga buoyancy check is always a good idea in a new environment prior to your dive.
Good luck
Steve
Good luck
Steve
The Kraken
He Who Glows in the Dark Waters (ADVISOR)
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Scuba Instructor
Divemaster
As a rule of thumb, about 3% of your total gross salt water diving weight.
That is, if you and all your gear weighs in ata 200 pounds, then the amount of weight you want to drop is 200 x .03 which equals 6 pounds.
the K
That is, if you and all your gear weighs in ata 200 pounds, then the amount of weight you want to drop is 200 x .03 which equals 6 pounds.
the K
Last edited:
Dave:
Keep in mind that the amount of weight you are using right now is a function of lots of factors including your weight, density (muscle versus body fat), surface area, weight/density of gear and of course the thickness of your wetsuit. No two people or gear configurations are exactly alike. Rules of thumb are exactly just that, easy estimates that get most people close to what they need.
Therefore, be sure to have some small weight increments on your belt or in your bc (in case you need to shed a little) and carry an extra 1-2 pounds of weight (in case you need to add). I personally use ankle weights when I need to add a little weight...
All that said, there is a fun little Bouyancy calculator at Piscesdivers.com that provides weight conversions from salt to freshwater and vice versa.
PADI scuba lessons in Rochester NY at Pisces School of Dive
You might want to give the calculator a try and see how close it comes to both your in water results and the very good rules of thumb NVScubaSteve gave you. It will be interesting to see how close they all come to each other... Let us know!
Dive safe and enjoy...
P
Keep in mind that the amount of weight you are using right now is a function of lots of factors including your weight, density (muscle versus body fat), surface area, weight/density of gear and of course the thickness of your wetsuit. No two people or gear configurations are exactly alike. Rules of thumb are exactly just that, easy estimates that get most people close to what they need.
Therefore, be sure to have some small weight increments on your belt or in your bc (in case you need to shed a little) and carry an extra 1-2 pounds of weight (in case you need to add). I personally use ankle weights when I need to add a little weight...
All that said, there is a fun little Bouyancy calculator at Piscesdivers.com that provides weight conversions from salt to freshwater and vice versa.
PADI scuba lessons in Rochester NY at Pisces School of Dive
You might want to give the calculator a try and see how close it comes to both your in water results and the very good rules of thumb NVScubaSteve gave you. It will be interesting to see how close they all come to each other... Let us know!
Dive safe and enjoy...
P
Last edited:
Merlin830
Registered
Freshwater = 62.4 lbs/ cubic ft
Saltwater = 64.0 lbs/cubic ft
Since good old Archimedes determined that the bouyancy is the total weight of the displaced fluid then:
62.4/64.0=.975 So multiply .975 times the weight you use and you will be there.
Saltwater = 64.0 lbs/cubic ft
Since good old Archimedes determined that the bouyancy is the total weight of the displaced fluid then:
62.4/64.0=.975 So multiply .975 times the weight you use and you will be there.
Mkutyna:
Surface area determines the number of square feet of wetsuit material... The more and thicker neoprene you are wearing the more weight you need to compensate...
P
Surface area determines the number of square feet of wetsuit material... The more and thicker neoprene you are wearing the more weight you need to compensate...
P
Being a new diver, chances are you are a touch overweighted anyway. Just drop 5-6 lbs off and have some fun.
Once you really have a good handle on your bouyancy you can get the weight closer for each situation by doing a good bouyancy check, post dive with little air left in your tank. (Search around for some really good threads on how to do this)
Once you really have a good handle on your bouyancy you can get the weight closer for each situation by doing a good bouyancy check, post dive with little air left in your tank. (Search around for some really good threads on how to do this)
don Francisco
Contributor
Why use rules of thumb or estimates when an exact answer is available.
Assuming you were correctly weighted in salt water, and are using the same equipment, especially wetsuit and tank, use Merlins magic formula and drop 2.5% (or 1#/40) of your total weight. That's you, your equipment, your tank and weights included.
Obviously teh formula only works if there are no significant changes, but if there are you'd be compensating for salt water too.
Assuming you were correctly weighted in salt water, and are using the same equipment, especially wetsuit and tank, use Merlins magic formula and drop 2.5% (or 1#/40) of your total weight. That's you, your equipment, your tank and weights included.
Obviously teh formula only works if there are no significant changes, but if there are you'd be compensating for salt water too.
this might give a bit of insight to the dramatic difference,
when i was diving in the Mediterranean i had a
5mm shorty and a 6L aluminum tank i used 8kg
when i went for a dive in fresh water i had a
3mm shorty and a 10L steel tank i used no wieght
i was really shocked by this, i knew i wouldnt need much but... no weight!!
when i was diving in the Mediterranean i had a
5mm shorty and a 6L aluminum tank i used 8kg
when i went for a dive in fresh water i had a
3mm shorty and a 10L steel tank i used no wieght
i was really shocked by this, i knew i wouldnt need much but... no weight!!
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