How precise is everyone when mixing salt?

[ackshee]

I see some sources saying 1/2 cup per gallon, other sources saying 39 grams per litre.

How many of you use a balance to weigh out X grams of salt? How many of you actually measure out X litres of water? How many of you just wing it, and then test the salinity and adjust it?


I understand that, regardless, it's important to test the specific gravity before using it. I'm just curious how much time and effort people put into this.

 

[DED65]

I just guess at the amount and adjust. Little more salt, little more water is easier than measuring water and weighing salt!

 

[cilyjr]

I always mix to 1.025 on a Milwaukee refractometer. I don't weigh it going in.

 

[Gumbies R Us]

Usually, I just do a rough estimate with salt and water in my bucket; I start low on salt and slowly raise it to the number I want it to be.

 

[Mr. Mojo Rising]

After doing it so many time, I just eyeball it now, I'm usually pretty accurate. (of course I test before using)

 

[Tommy B]

I weigh in grams on a kitchen scale and use a refractometer to check after the batch mixes.

 

[danimal1211]

I typically mix up the same amount each time. I marked a line on my bucket so that I add water then salt and fill to line then test. It gets me close if not spot on each time.

 

[ackshee]

Thanks for weighing in everyone (no pun intended)

Obviously, all that matters is that the final salinity is correct. So I don't think there's any wrong way to do it. But I'm a little bit surprised by all you eyeballers! I get the impression that reefkeepers are very precise people in general.

 

[Cell]

I eyeball it and usually end up between 30-35 ppt first try.

 

[Sophie"s mom]

I see some sources saying 1/2 cup per gallon, other sources saying 39 grams per litre.

How many of you use a balance to weigh out X grams of salt? How many of you actually measure out X litres of water? How many of you just wing it, and then test the salinity and adjust it?


I understand that, regardless, it's important to test the specific gravity before using it. I'm just curious how much time and effort people put into this.

I use a measuring cup, 2 1/2 cups to a 5 gallon bucket. But after 24 hours I check and guess at adjusting.

 

[rhitee93]

I never know exactly how much water is in my salt mixing barrel, and I rarely start with it empty, so there is always a bit of residual salt. However, I am an engineer and accuracy is in my blood, so I do the following:

When it is time to mix salt, I fill the salt water storage barrel (55gal) from my RODI water storage barrel. Then I measure and record the salinity. (It will be near zero)

Next I add 4.5kg of salt (measured to the gram) and allow it to mix for 24 hours. Once mixed I measure the salinity again.

Now I know how much the salinity increased because of the 4.5kg salt. This allows me to calculate exactly how much salt I need to add to that particular barrel to get to the target salinity.

 

[aSaltyKlown]

I use a 20 gallon brute with a line marked at 20 and 10 gallons. At times I top it off each week, about 10 gallons. Sometimes a couple weeks pass before a top off so I'm never sure how much fresh I'm adding. If it's near the 10g mark, I'll add in 9 1/2 cups and check after an hour or so. If almost empty I'll add 18 1/2 cups. I don't have much room to adjust if I add too much salt, so I always go under.

 

[JayM]

I use a 16oz plastic cup. 4 1/2 scoops to 20 gallons, check salinity and add a bit more salt as needed.

 

[aSaltyKlown]

I never know exactly how much water is in my salt mixing barrel, and I rarely start with it empty, so there is always a bit of residual salt. However, I am an engineer and accuracy is in my blood, so I do the following:

When it is time to mix salt, I fill the salt water storage barrel (55gal) from my RODI water storage barrel. Then I measure and record the salinity. (It will be near zero)

Next I add 4.5kg of salt (measured to the gram) and allow it to mix for 24 hours. Once mixed I measure the salinity again.

Now I know how much the salinity increased because of the 4.5kg salt. This allows me to calculate exactly how much salt I need to add to that particular barrel to get to the target salinity.

Similar, situation for me but not nearly as accurate!!

 

[Tired]

I just use a measuring cup, trying to err on the side of too much, then check with a refractometer. I'm usually pretty close, and too salty is easy to correct if I'm not. When I've mixed it without enough salt, I tend to eyeball how much more to add, and usually surprise myself with how close I get.

 

[rtparty]

By weight. Every time. Takes all the guesswork out of it and with a good salt, you don’t even have to check salinity.

On my brute can I weighed the water initially that was added and marked it. That way I knew my exact volume of water.

And then to really take the guesswork out of everything, get the Tropic Marin hydrometer and stop using refractometers that need constant adjustment and calibration.

 

[fish farmer]

I measure out freshwater by the gallon, then add a 1/2 cup of salt per gallon into my mixing container which usually has a gallon or two at all time. I generally mix up 5 to 6 gallons at a time, let it mix overnight with flow and heat. I check the day of water change with a refractometer and may have to adjust up a bit.

 

[exnisstech]

I've read humidity can change the weight. Not sure if that's true or not but it made sense. I use a measuring cup. I mix in a brute with a float valve. Filled to shut off 15 cups salt yields 28g at 1.025 using IO. I've never gotten 1.025 using 1/2c per gallon

 

[jhadaway]

I measure in grams and have marked the inside of my Brute. no chances

 

[Reefer Matt]

I use a brute can to mix. I discovered that five full scoops of a plastic popcorn container gets me to 1.025 sg. I check it before use. Sometimes my scoops aren’t all equal, and I adjust with more water or salt. No harm done if it isn’t mixed precisely at first. Just check and adjust before use. I also recommend adjusting alkalinity if you have sps or lps coral as well.