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Old 01-14-2004, 08:52 PM   #11
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if its off do you guess how much more salt or fresh water to add
YES!

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therefore if you add 25g of salt mix to 1000cc of water at 60F the water weighs 1025g. 1025g/1000cc (m/v) the final product is sg of 1.025.
Not necessarily true.
Specific gravitycompares the density of a mineral to the density of water. If a mineral has a SG of 2, then it is twice as dense as water. If a mineral has a SG of 3 then it is three times as dense as water. A salt MIX is made of salt and many other minerals, therefore the same quantity of different mixes could yield a different SG at the same temperature.

I start with the directions on the package, mix till disolved, wait a couple of hours, test with a refractometer, then adjust if needed.
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Old 01-15-2004, 09:57 AM   #12
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The specific gravity of a substance is a comparison of its density to that of water A marine salt mix contains not only salt but many minerals, each with their own SG.

Specific gravity compares the density of a mineral to the density of water. If a mineral has a SG of 2, then it is twice as dense as water. If a mineral has a SG of 3 then it is three times as dense as water.

Because the various commercial sw mixes contain differing amounts of the numerous trace minerals, a given quantity of mix from different manufacturers or even different batches from the same manufacturer will produce a slightly different SG.

Testing a mix with a refractometer is the only way to be truly accurate.
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Old 01-15-2004, 10:10 AM   #13
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Specific gravitycompares the density of a mineral to the density of water.
i said the exact same thing.
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sg is the density(mass divided by volume) divided by the density of pure water at 60F (1.000).
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Not necessarily true.
100% true except for one factor. that i chose to leave out, for simplicities sake, adding the volume of the salt mix to the volume of the water. i would suspect that different salt mixes may have radically different concentrations when using a measuring cup (the amount of air, grain size, water content). but i believe that when measuring the "true density" of different salt mixes one would find that they very similar.

im not trying to start an argument, but i do like a good debate. that is how good questions are created

my whole point of this post was to stop guessing and be more scientific about my approach. i used to work in a lab for sony mixing chemicals and such (not much schooling in this subject, just worked my way up the ladder) and everything was a known, to some extent. i was able to fill a 500l tank with di water in two hours. this was in a chart. you set your watch or else get a mop. if you couldnt find a chart or table you made your own. to achieve a specific concentration you read the specs, you measured and mixed.
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Peppermint Shrimp:
Crush two tbs minced mint leaves (no stems) with the juice of two limes, two tbs of sugar and a shot of light rum. Marinade eight cleaned jumbo shrimp for two hours in fridge or overnight (overnight is best). Skewer and salt shrimp. Broil or grill over medium high heat until shrimp become opaque (apx. two and a half min per side). Serve with black beans cooked with garlic, green onions, bacon and topped with a slice of lime.
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Old 01-15-2004, 10:19 AM   #14
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whoa, this is getting way to technical for my simple mind!
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Old 01-15-2004, 10:19 AM   #15
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ause the various commercial sw mixes contain differing amounts of the numerous trace minerals, a given quantity of mix from different manufacturers or even different batches from the same manufacturer will produce a slightly different SG.
i agree but trace usually means barely identifiable. this could mean that a pinch of something could be added to a five gallon bucket. having an effect that probably even the most accurate means of testing density would would show know change.

im still working on my table.
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Peppermint Shrimp:
Crush two tbs minced mint leaves (no stems) with the juice of two limes, two tbs of sugar and a shot of light rum. Marinade eight cleaned jumbo shrimp for two hours in fridge or overnight (overnight is best). Skewer and salt shrimp. Broil or grill over medium high heat until shrimp become opaque (apx. two and a half min per side). Serve with black beans cooked with garlic, green onions, bacon and topped with a slice of lime.
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Old 01-15-2004, 10:24 AM   #16
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whoa, this is getting way to technical for my simple mind!
sorry i just wantedknow how much pure water needs to be added to five gallons of salt water to change the sg from 1.027 to 1.025. with out guessing. thought maybe someone had figuered this out already
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Peppermint Shrimp:
Crush two tbs minced mint leaves (no stems) with the juice of two limes, two tbs of sugar and a shot of light rum. Marinade eight cleaned jumbo shrimp for two hours in fridge or overnight (overnight is best). Skewer and salt shrimp. Broil or grill over medium high heat until shrimp become opaque (apx. two and a half min per side). Serve with black beans cooked with garlic, green onions, bacon and topped with a slice of lime.
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Old 01-15-2004, 11:17 AM   #17
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im still working on my table.
Please post it when complete. Don't forget to take temperature into account too.
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Old 01-15-2004, 11:30 AM   #18
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will do
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Peppermint Shrimp:
Crush two tbs minced mint leaves (no stems) with the juice of two limes, two tbs of sugar and a shot of light rum. Marinade eight cleaned jumbo shrimp for two hours in fridge or overnight (overnight is best). Skewer and salt shrimp. Broil or grill over medium high heat until shrimp become opaque (apx. two and a half min per side). Serve with black beans cooked with garlic, green onions, bacon and topped with a slice of lime.
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Old 02-23-2004, 12:02 AM   #19
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Sorry its been so long.
Ive had no success in coming up with a formula. after a good bit of research, boning up on my chemistry, and a lot of pencil lead and eraser leavings. ive come up with nothing. i gave up. ther was definately something that i repeeatedly left out?
no matter, it beat twideling my thumbs.

i did buy a scale at a cooking store and it turned my guesses into very accurate assumptions. for instance, when mixing change water i add 1620g of IO to a ten gallon tank of water and its right on the money every time. every thing i add to my tank other than food i now weigh and record in a log book. it may seem rather anal retentive but now when something goes a bit awry i can honestly know that its not something that i added in excess. i would recomend a scale.

sorry i never came up with an accurate table.

may i have some tabasco sauce with my hat!!!
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Peppermint Shrimp:
Crush two tbs minced mint leaves (no stems) with the juice of two limes, two tbs of sugar and a shot of light rum. Marinade eight cleaned jumbo shrimp for two hours in fridge or overnight (overnight is best). Skewer and salt shrimp. Broil or grill over medium high heat until shrimp become opaque (apx. two and a half min per side). Serve with black beans cooked with garlic, green onions, bacon and topped with a slice of lime.
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Old 02-23-2004, 12:03 AM   #20
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Sorry its been so long.
Ive had no success in coming up with a formula. after a good bit of research, boning up on my chemistry, and a lot of pencil lead and eraser leavings. ive come up with nothing. i gave up. ther was definately something that i repeeatedly left out?
no matter, it beat twideling my thumbs.

i did buy a scale at a cooking store and it turned my guesses into very accurate assumptions. for instance, when mixing change water i add 1620g of IO to a ten gallon tank of water and its right on the money every time. every thing i add to my tank other than food i now weigh and record in a log book. it may seem rather anal retentive but now when something goes a bit awry i can honestly know that its not something that i added in excess. i would recomend a scale.

sorry i never came up with an accurate table.

may i have some tabasco sauce with my hat!!!
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Peppermint Shrimp:
Crush two tbs minced mint leaves (no stems) with the juice of two limes, two tbs of sugar and a shot of light rum. Marinade eight cleaned jumbo shrimp for two hours in fridge or overnight (overnight is best). Skewer and salt shrimp. Broil or grill over medium high heat until shrimp become opaque (apx. two and a half min per side). Serve with black beans cooked with garlic, green onions, bacon and topped with a slice of lime.
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