Measuring Salinity / Specific Gravity in Aquariums

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ScubaFish802

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Hi Jay - maybe I'm blind - but I cant get to the article - the link above goes to another page - which contains a link to 'original content' - and 'about the author' - When you click Original content nothing happens? @Jay Hemdal
Hey, it looks like if you scroll all the way down you can download the article, I am on my phone, so can’t confirm.. but worth a shot!
 

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ReefLife_Guy

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Hi Jay - maybe I'm blind - but I cant get to the article - the link above goes to another page - which contains a link to 'original content' - and 'about the author' - When you click Original content nothing happens? @Jay Hemdal
Have to download the pdf it is on the right hand side if you are on a computer.

1655476446410.png
 

brandon429

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Well I thought it was great. As someone who has used the same dip and read since 2010 I'm glad they weren't slighted here in favor of refracts

I rinse mine out with distilled after each use/ toss back in drawer. I calibrated twice over this time at the pet store it's close enough. I don't need a fancy device these got us through the 90s just fine. The article mentions times we may need more precision, thought that was great. Solid reading.
 

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The article not include the water temperatur as a parameter when measuring the salinity to calculate actual saliniy.
I expect that a refractometer with ATC give the actual salinity since as it adjust for water tempertur. Is that correct ?
I use the salinity correction calculator from Reefapp when using a lab grade glass hydrometer.
 

MnFish1

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The article not include the water temperatur as a parameter when measuring the salinity to calculate actual saliniy.
I expect that a refractometer with ATC give the actual salinity since as it adjust for water tempertur. Is that correct ?
I use the salinity correction calculator from Reefapp when using a lab grade glass hydrometer.
Correct
 

Randy Holmes-Farley

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True salinity, of course, does not ever change with temperature.
However, nearly all methods of salinity determination do get impacted by temperature changes.

Some devices (ATC refractometer, conductivity meters, and swing arm hydrometers) try to make that needed correction automatically, while others such as glass hydrometers leave that to the user.
 
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Jay Hemdal

Jay Hemdal

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The article not include the water temperatur as a parameter when measuring the salinity to calculate actual saliniy.
I expect that a refractometer with ATC give the actual salinity since as it adjust for water tempertur. Is that correct ?
I use the salinity correction calculator from Reefapp when using a lab grade glass hydrometer.

Yes - refracts need to have ATC. Hydrometers are also affected by temperature, but most (all) are adjusted for home aquarium temperatures.

Jay
 

OldRed1

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As a new reefer, this article helped me to make sense of all the various recommendations I have received on how to test salinity. I recently purchased my first refractometer from BRS, and this article gave me a much better understanding of how it will work. Thanks, Jay!
 
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Jay Hemdal

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My eyes are not so great..so could someone recommend who cant use the refractometer he has.A pen tester that is maybe good for Tds as well .Hmm wondering if my water in the mountains reads 0 Total dissolved Solids can i skip the Rodi?

TDS is essentially PPM. So, if you get a reading of 0 TDS on a meter that is designed to read that low (+ or - 1 or 2 tds units) then that water is pretty low in dissolved solids. I've never seen ground water that low, but maybe in the mountains?

If you get a zero reading on a salinity meter, that is reading in parts per thousand, and so it may not be low enough to use without RODI.

A lot of people are using the Hanna salinity checker for their aquariums (but you would still need a TDS pen).

Jay
 
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Randy Holmes-Farley

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I don’t think there is any natural 0 ppm tds water in a stream or well, but the tds doesn’t matter anyway. It’s what is there that matters. If you take 0 ppm tds water and run it through copper household pipes, it is likely to not be usable due to realeased copper.
 

Randy Holmes-Farley

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Thank you ya ill get a Rodi unit /maybe ill just go with a 4 stage...if you are saying everyone nomatter what needs to run tap through a unit..ya i have copper pipes but the house is only 20 years old..well 23.Im in Colorado near Colorado springs.

I never said such a thing, but I think it’s a good plan. Many people use tap water ok and many cannot. Unless you test the water, there’s no way to know if it is adequate or not.
 

Lee adams

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Reef.

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The article not include the water temperatur as a parameter when measuring the salinity to calculate actual saliniy.
I expect that a refractometer with ATC give the actual salinity since as it adjust for water tempertur. Is that correct ?
I use the salinity correction calculator from Reefapp when using a lab grade glass hydrometer.
I found the salinity correction charts inaccurate, especially if the temp is not close to the temp the hydrometer was calibrated.
Have you tried checking the chart for accuracy?
 

Reef.

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Ok after i Calibrated my and it reads 83...since i have no idea if this is ok to use without a Rodi unit..guess ill just get a 100 $ one and maybe get some batteries for my Rainbird tds meter to check one more time...however 83 is very low.

you don’t know what that 83 is, yes it’s on the low side for tap water but when people change their rodi filters at 1 tds or before, 83 doesn’t seem so low anymore.
 
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