? Salt per Gallon = 1.009 ??
- Thread starter shookbrad
- Start date
paulamrein
New member
I've always just used my refractometer to get my reading until I found a cup that would give it to me exactly in a 5 gallon bucket. If you are trying hypo without a refractometer you may run into some trouble with it as you have to keep a measure of it on a daily basis. A lab grade hydrometer has been known to keep a good read but never trust a swing arm when dealing with such low salinity.
I just asked a simple question. I do not want to have to add some salt and test. add more and test. I know I need to always test before using but I want a good close estimate to start at. I am not looking for lectures on how I should always use a refractometer or hydrometer. I have this covered. I know how to do that.
I do appreciate the concern from my fellow reefers. I do know I need to check constantly and am doing so. It has been over a year since I have had new fish requiring the Hypo treatment so I could not remember the measurement.
Here is the answer I got from Marine land(maker of reef crystals).
it takes approximately 1/5 a cup of salt per gallon to get a salinity of 1.009.
Simple question simple answer.
I do appreciate the concern from my fellow reefers. I do know I need to check constantly and am doing so. It has been over a year since I have had new fish requiring the Hypo treatment so I could not remember the measurement.
Here is the answer I got from Marine land(maker of reef crystals).
it takes approximately 1/5 a cup of salt per gallon to get a salinity of 1.009.
Simple question simple answer.
paulamrein
New member
How old are you? Do you deal with the general public on a daily basis? simple criticism is bound to happen where ever you go, I wouldn't have taken any offense to anything that was said. But hey, you have been doing salt for 4 years now, you've got it down to a science, you don't need any help from anyone.
pescadero
In Memoriam
if you ask questions openly in a public forum, you're likely to get answers that you like and some answers that you don't like. that's the nature of the beast.
a simple answer of approximately 1/5 of a cup will get you close enough to kill your fish if you err on the low side. this is actually a very complex question that doesn't lend itself well to simple answers. be sure to take actual measurements, as there is zero margin for error at an SG of 1.009.
my recommendation is to learn to do the calculations yourself. the easiest way to do your calculations is to work in parts per thousand instead of specific gravity. then anyone with basic math skills can perform the calculations. you can check your work online with the saltyzoo salinity calculator.
once you know how much salt you will need that's only the beginning. getting an accurate result is actually a lot harder than it sounds, and there really is no substitute for the method of successive approximations.
a simple answer of approximately 1/5 of a cup will get you close enough to kill your fish if you err on the low side. this is actually a very complex question that doesn't lend itself well to simple answers. be sure to take actual measurements, as there is zero margin for error at an SG of 1.009.
my recommendation is to learn to do the calculations yourself. the easiest way to do your calculations is to work in parts per thousand instead of specific gravity. then anyone with basic math skills can perform the calculations. you can check your work online with the saltyzoo salinity calculator.
once you know how much salt you will need that's only the beginning. getting an accurate result is actually a lot harder than it sounds, and there really is no substitute for the method of successive approximations.
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shookbrad,
That really isn't a simple question. I'm working on an article on "salt content of aquariums" for TFH and as I've researched it, I've been amazed at how many problems can arise from this simple sort of question. For example, as Kevin pointed out, different brands of salt will measure out differently. If you tried the more precise method of weighing the salt out on a gram scale you would soon discover that salt is hydroscopic, it absorbs moisture from the air - making weighing small amounts accurately literally impossible.
Then there is the whole issue of precision and accuracy of your measuring divices. At 1.009 there is ZERO margin of error for accuracy - if your device is reading even one SG unit high, you may lose fish. I tested 15 hydrometers from four different manufacturers and found a variance of 4.5 specific gravity units for lowest to highest.
The best method would be to use a standardized ATC refractometer (not just standardidized to distilled water, but to a 35ppt standard as well) - mix up some water to 1.012 and then add small amounts of freshwater to work down to 1.009. It is VASTLY more difficult to accurately mix up a small amount of seawater than to make up a larger batch.
JHemdal
That really isn't a simple question. I'm working on an article on "salt content of aquariums" for TFH and as I've researched it, I've been amazed at how many problems can arise from this simple sort of question. For example, as Kevin pointed out, different brands of salt will measure out differently. If you tried the more precise method of weighing the salt out on a gram scale you would soon discover that salt is hydroscopic, it absorbs moisture from the air - making weighing small amounts accurately literally impossible.
Then there is the whole issue of precision and accuracy of your measuring divices. At 1.009 there is ZERO margin of error for accuracy - if your device is reading even one SG unit high, you may lose fish. I tested 15 hydrometers from four different manufacturers and found a variance of 4.5 specific gravity units for lowest to highest.
The best method would be to use a standardized ATC refractometer (not just standardidized to distilled water, but to a 35ppt standard as well) - mix up some water to 1.012 and then add small amounts of freshwater to work down to 1.009. It is VASTLY more difficult to accurately mix up a small amount of seawater than to make up a larger batch.
JHemdal
As previously stated --- different salt mixtures will give you different results so there was no "simple" answer to your question.
An easy method to get an approximate 1.009 SG is to mix up a regular batch of SW to the std reef level of 1.026 using whatever "cups per gallon" ratio works with that salt brand .. and then use a ratio of 1/3 SW to 2/3rd FW .. should get you close.
