Measuring Salinity

Mbargas

Candiru
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Jul 8, 2016
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What is the best device for measuring salinity in the lower range? I mean from about 1 ppt to 5 ppt.
I have both a hydrometer and refractometer, but neither one is very precise in the lower range.
 

Mbargas

Candiru
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Jul 8, 2016
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With such a resounding response, I had to do my own inquiry. As all of you know hydrometers and refractometers do a good job with salinity/SG in the higher ranges, but not in the lower ranges. I mean, how would you distinguish between 1 And 2 ppt?
It seems to me that TDS monitors are the answer. There are a number of inexprnive ones hat will measure dissolved solids between 0 and 4999 ppm (4.999 ppt)
Certainly not useful for higher salinities, but much more precise in the lower range.
 
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CastellClan007

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Jul 20, 2019
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Hey, I have a question if you still get updates on this old thread... Well, 2 questions.
1: how would I go about finding the appropriate level of TDS for a given salinity?
2: how would I adjust for solids, such as calcium or trace metals, other than nacl that may be dissolved in the water? I have a TDS meter that measures via conductivity, but I'm not sure what & how different things might affect the reading.

I'm glad you posted this, because I've been struggling with how to measure for an F8 Puffer tank I've set up. Was looking at refractometers but was unsure if one calibrated on only one point (which I think is usually at high salinity) would work for an sg of around 1.008.
 
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tlindsey

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Hey, I have a question if you still get updates on this old thread... Well, 2 questions.
1: how would I go about finding the appropriate level of TDS for a given salinity?
2: how would I adjust for solids, such as calcium or trace metals, other than nacl that may be dissolved in the water? I have a TDS meter that measures via conductivity, but I'm not sure what & how different things might affect the reading.

I'm glad you posted this, because I've been struggling with how to measure for an F8 Puffer tank I've set up. Was looking at refractometers but was unsure if one calibrated on only one point (which I think is usually at high salinity) would work for an sg of around 1.008.

Welcome aboard
twentyleagues twentyleagues
Gourami Swami Gourami Swami
 
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duanes

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I used to use Hach Conductivity/ Salinity meter for judging salinity of 3ppt when treating for ick.
They worked well at low range, don't know todays prices, but I would imagine there are affordable ones, but then again, you always get what you pay for.
For example, buy a cheap heater, get cooked fish. Some things are important enough to spend a few extra bucks for.
Images for Hach conductivity meter
 

PYRU

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Apr 8, 2015
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Hey, I have a question if you still get updates on this old thread... Well, 2 questions.
1: how would I go about finding the appropriate level of TDS for a given salinity?
2: how would I adjust for solids, such as calcium or trace metals, other than nacl that may be dissolved in the water? I have a TDS meter that measures via conductivity, but I'm not sure what & how different things might affect the reading.

I'm glad you posted this, because I've been struggling with how to measure for an F8 Puffer tank I've set up. Was looking at refractometers but was unsure if one calibrated on only one point (which I think is usually at high salinity) would work for an sg of around 1.008.
I could of swore I used a refractor back in the day for my F8. Here's an accurate meter though.

 

duanes

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I could of swore I used a refractor back in the day for my F8. Here's an accurate meter though.

That looks like a nice unit, especially with the auto calibration.
 

local hero

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Sep 11, 2006
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...in my head
Ohaus makes a decent meter for around $65 (Ohaus ST10S).
 
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