# Refractometer



## poobar (Feb 20, 2011)

Has anyone ever purchased one of these off E-Bay??

http://www.ebay.ca/itm/RHS-10ATC-Sa...Television_Test_Equipment&hash=item45fe473c1c

I am curious if they are worth while or if I am wasting my money??


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## darthvictor (Aug 16, 2011)

I got mine on ebay, works great  You should test it with room temp. RO water once you get it, calibrate it at zero; then all is good


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## Chromey (Sep 25, 2010)

i cant see something like this going wrong, But i would be afraid of how cheap it is.


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## newfish (Nov 15, 2011)

I have some calibrating solution if needed. 

Peter


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## amdninjaboy (Dec 9, 2011)

I was amazed when I got mine.. My floating arm hydro said water was at 1.022... Refrac said 1.026... DOH!! Well worth the money..

Shane.


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## bigfishy (Jun 19, 2009)

amdninjaboy said:


> I was amazed when I got mine.. My floating arm hydro said water was at 1.022... Refrac said 1.026... DOH!! Well worth the money..
> 
> Shane.


Since it is off by 0.004, is that good or bad?


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## poobar (Feb 20, 2011)

That's bad. It all depends on which one is correct though!


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## amdninjaboy (Dec 9, 2011)

The refrac is correct.. Its not a big deal really if you know but I had no idea.. Also im running FOWLR, so its not hurting much other than im using more salt than I needed to. I run my tank at 1.020 now.. If I had a reef and went by the hydro it would have said I was at 1.026 but it would have been 1.030..
If you just go with a floating arm type I would suggest you check it with someone who uses a refrac, if you know its out by .004 then you can take that into account..

Shane.


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## TankCla (Dec 31, 2010)

poobar said:


> Has anyone ever purchased one of these off E-Bay??
> 
> http://www.ebay.ca/itm/RHS-10ATC-Sa...Television_Test_Equipment&hash=item45fe473c1c
> 
> I am curious if they are worth while or if I am wasting my money??


Have you bought it? Is it good? I want to buy one similar.


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## poobar (Feb 20, 2011)

Yes, went out and got it.

The actual Refractometer works amazingly well for the price. You can tell that the build quality isn't up to North American standards.
The case that comes with it, the zip was broke when I got it. Stuff like that.

But for what it does at the price, I don't care.
The actual product works amazingly well!
Calibrate to 0 with RO water and off you go.

I was very plesantly surprised.


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## darthvictor (Aug 16, 2011)

go for it. I will first use a plastic bag fill it with some RO water and float it in ur tank first, then use that RO water which is now same temperature as ur tank water to calibrate the refractometer to zero. I know it say ATC, but just to be sure. That's what I did for mine


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## Chris S (Dec 19, 2007)

darthvictor said:


> I got mine on ebay, works great  You should test it with room temp. RO water once you get it, calibrate it at zero; then all is good


You can't calibrate a refractometer with RO water, you need to use a calibration solution.


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## darthvictor (Aug 16, 2011)

Chris S said:


> You can't calibrate a refractometer with RO water, you need to use a calibration solution.


oh? isn't a refractometer work with the light reflect index?


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## Kooka (Feb 8, 2011)

Chris S said:


> You can't calibrate a refractometer with RO water, you need to use a calibration solution.


I believe you can use RO water, or even distilled water to calibrate the refractometers that are sold on eBay. I think even the instructions that come with them mention it. The actual refractometer itself is basically a glass prism, so I'm not sure why a calib solution would be necessary.


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## Chris S (Dec 19, 2007)

If your refractometer is measuring low, how can you tell using RO? It will just show a salinity of 1.000. It can't show you a salinity deficit. You need to calibrate it using a proper solution, despite what the instructions on ANY refractometer says.


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## wtac (Mar 17, 2006)

Refractometers were first used in brining aspect of cheese making and pickling industry. A base brine solution is just salt (NaCl/sodium chloride) and water and the scale is suited for determining the concentration of NaCl in solution by how much the light bends. Saltwater in the ocean and aquariums the salt is ~95% NaCl, the light will not bend the same. 

Calibrating to a apecific gravity (SG) of 1 with RO/DI, distilled or Millipore(TM) water is fine for salt that is 100% NaCl, but not for our reefing purposes. For that, you have to use a SG 35 solution.

HTH


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## Chris S (Dec 19, 2007)

This is why Wilson is smarter than me


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## Redddogg69 (Oct 1, 2011)

Chris S said:


> This is why Wilson is smarter than me


That and the childhood accident


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## Chris S (Dec 19, 2007)

I was told that wasn't an accident, wth?


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## TankCla (Dec 31, 2010)

wtac said:


> Refractometers were first used in brining aspect of cheese making and pickling industry. A base brine solution is just salt (NaCl/sodium chloride) and water and the scale is suited for determining the concentration of NaCl in solution by how much the light bends. Saltwater in the ocean and aquariums the salt is ~95% NaCl, the light will not bend the same.
> 
> Calibrating to a apecific gravity (SG) of 1 with RO/DI, distilled or Millipore(TM) water is fine for salt that is 100% NaCl, but not for our reefing purposes. For that, you have to use a SG 35 solution.
> 
> HTH


I got my refractometer today. 
Where can I find SG 35 solution to calibrate it? Or can someone help me with calibration?

Thank you!

Sent from my BlackBerry using Tapatalk


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## darthvictor (Aug 16, 2011)

TankCla said:


> I got my refractometer today.
> Where can I find SG 35 solution to calibrate it? Or can someone help me with calibration?
> 
> Thank you!


I would like to know where I can find some as well, thanks


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## wtac (Mar 17, 2006)

SUM sells SG 35 calibration solution.


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## TankCla (Dec 31, 2010)

wtac said:


> SUM sells SG 35 calibration solution.


Thank you!

12.99$ - 60 ml (lifetime)

Did the calibration yesterday with RO water, and today with calibration solution 35. It was off by 0.002.

I don't want to talk about my hydrometer, off by 0.003.


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## JulieFish (Apr 8, 2011)

was it 0.002 too high or too low with just the distilled, if you recall?


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## TankCla (Dec 31, 2010)

0.002 above the control solution.


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## Chris S (Dec 19, 2007)

I assume you came by when I was mind numbingly glueing ricordea to frag plugs today then =)


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## TankCla (Dec 31, 2010)

Yes. And asked about anemone.


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